The Lifeline: 1939, the Athenia and the Return of the Convoy

On the first evening of the war a U-boat torpedoed a crowded liner off the coast of Ireland, and Britain concluded that the Germans meant to starve it as they had tried to in 1917. Within two weeks the convoys were back. The first winter showed both sides how much they had misjudged the war at sea.

Why it mattered

The Battle of the Atlantic was the longest continuous campaign of the Second World War. It began on the first day of Britain’s war, 3 September 1939, and it did not end until German U-boats made their last attacks in the first week of May 1945. Every other campaign the Western Allies fought in Europe depended on it. The armies that went ashore in North Africa, Sicily, Italy and Normandy, the bombers that flew from English airfields, and the food that kept the British population alive all crossed the Atlantic in merchant ships. If the ships could not cross, none of the rest could happen.

The first nine months set the pattern for everything that followed. The British put back into service the convoy system that had saved them in 1917, and it worked. The Germans discovered that they had gone to war with too few U-boats and, as it turned out, with torpedoes that often did not explode. Both navies learned that their prewar confidence had been misplaced: the British in their underwater detection gear, ASDIC, and the Germans in their weapons. And from the sinking of the liner Athenia on the first evening, the war at sea was fought with fewer restraints than either side’s lawyers had planned for.

Years later Winston Churchill, who as First Lord of the Admiralty ran the Royal Navy’s political side through this first winter, wrote that nothing else in the war had frightened him as the U-boats did. This chapter tells how that fight started.

In their words

The only thing that ever really frightened me … was the U-boat peril.

An island that ate from the sea

Britain in 1939 was a crowded industrial island that could not feed itself or run its factories from its own resources. Nearly all its oil, much of its food, and most of the raw materials of its war industry came by sea. The British official historians of the war economy, W. K. Hancock and M. M. Gowing, record that by 1942 the country’s imports had fallen to “less than forty-two percent of the prewar average,” at a time when they were arriving at an annual rate of about 24½ million tons (Hancock and Gowing, British War Economy, ch. XIV). Those figures imply a prewar average of well over 55 million tons a year, more than a million tons a week. The figure most often quoted, that Britain needed more than a million tons of imports a week to survive and to fight, is of that order.

Even the reduced wartime figures were large. In June 1940 government departments were told to count on no more than 35 million tons of imports in the coming year, with 15 million tons of that set aside for food; in 1941 the actual total reached only 30.5 million tons, of which food was 14.7 million (Hancock and Gowing, ch. X). Every one of those tons had to arrive in a ship.

Britain had the ships. Roskill counts about 3,000 deep-sea dry cargo ships and tankers and about 1,000 coasters under the British flag in 1939, totaling 21 million tons, with an average of 2,500 at sea on any given day (Roskill, The War at Sea, vol. I, ch. IV). It was the largest merchant fleet in the world, and most of its trade came home through a few narrow approaches: the Western Approaches around Ireland, the English Channel, and the North Channel into the Clyde and the Mersey.

The lesson of 1917

The British had been close to defeat at sea once before. On 1 February 1917 Germany declared unrestricted submarine warfare, sending its U-boats to sink merchant ships on sight around the British Isles. Losses rose month by month. In April 1917 U-boats sank 860,334 gross tons of shipping by the German count and 867,834 by the British, the worst month of the First World War (Encyclopedia 1914–1918 Online, “Atlantic U-Boat Campaign”). At that rate the arithmetic of food and shipping pointed toward a British collapse within months.

What turned it was the convoy. For most of the war the Admiralty had resisted grouping merchant ships under escort, arguing that a large convoy would be an easier target, that merchant masters could not keep station, and that there were too few escorts. In late April 1917 it gave way, and convoys were introduced for inbound shipping. The effect was not that convoys fought off U-boats so much that they made the ocean look empty. Forty ships sailing together were scarcely more visible than one, and a U-boat that once could find a target every few hours along the shipping lanes now could search for days and see nothing. When it did find a convoy, it found escorts with it. Sinkings fell through the rest of 1917 and 1918.

Between the wars the Navy kept the lesson but not its reason. Convoy came to be seen as a measure for use only if the enemy again waged unrestricted warfare, rather than as the best way to find and fight submarines. Roskill notes that the Admiralty regarded convoy as “the best protection” against submarine and air attack and prepared for it, but that a shortage of escorts and cruisers meant ocean convoys could not be formed at once; at first ships were to rely on “evasive routing” (Roskill, vol. I, ch. IV).

Faith in ASDIC

One reason the interwar Navy felt it could wait was a device. In the last months of the First World War, British and French scientists began work on a way to detect a submerged submarine by sending out a pulse of sound and listening for the echo. The British called it ASDIC; the Americans later called their version sonar. By the 1930s it was fitted in British destroyers and sloops, and many officers believed it had taken away the submarine’s chief advantage, its invisibility. Roskill describes the Navy’s “confidence in the protection which asdic-fitted destroyers would provide to heavy ships” (Roskill, vol. I, ch. VI).

That confidence had two consequences. The first was that the Navy built too few escorts. In 1939 it had about 100 fleet destroyers and 101 escort destroyers and sloops across the whole Empire, 32 of them in the Western Approaches (Roskill, vol. I, ch. IV). Most of the fleet destroyers were needed with the battle fleet. The second was that the Navy did not seriously expect the submarine to fight on the surface at night, where ASDIC was of little use. That was exactly how Karl Doenitz meant to fight.

Doenitz and the U-boat arm in 1939

The Treaty of Versailles had forbidden Germany to own submarines; the Anglo-German Naval Agreement of June 1935 allowed it to build them again. From 1 January 1936 the new U-boat arm was led by Karl Doenitz, then a Kapitän zur See, as Führer der Unterseeboote (FdU) (uboat.net, “Befehlshaber der Unterseeboote”). Born in 1891, Doenitz had commanded UC-25 and UB-68 in the First World War, and on 4 October 1918 he lost UB-68 in the Mediterranean and spent about nine months as a British prisoner.

Doenitz drew two lessons from 1917 and 1918. A single submarine could not defeat a convoy and its escorts; several boats had to be brought together against it, directed by radio from a shore headquarters, in what came to be called the wolf pack. And a U-boat should attack on the surface at night, where its low silhouette was hard to see and ASDIC could not find it, using its diesel speed to get inside the convoy. He trained his crews in both through the late 1930s.

What he lacked was boats. Doenitz assessed that 300 ocean-going U-boats were needed for a war against Britain (Roskill, vol. I, ch. IV): as his reasoning is usually summarized, a third would be on patrol, a third on passage and a third refitting, and a hundred boats at sea could break British trade. The Navy’s leadership had other priorities. Grand Admiral Erich Raeder’s Z Plan, approved early in 1939, was built around battleships; in Roskill’s summary it would have produced 13 battleships, 33 cruisers, four carriers and some 250 U-boats, with 162 U-boats by 1943 and 247 by 1948. It was designed for a war that Hitler had told Raeder would not come before the mid-1940s.

At the end of August 1939 Germany had 56 completed U-boats by Roskill’s count (most sources give 57), of which ten were not fully operational. Eight were boats of about 700 tons that could reach Gibraltar or the Azores; 18 were 500-ton boats, the first Type VIIs, that could reach about 15 degrees West; and 30 were small Type IIs of about 250 tons, limited to the North Sea and British coastal waters (Roskill, vol. I, ch. IV). By 31 August, 39 U-boats had sailed for their waiting positions around the British Isles.

The Type VII became the workhorse of the Atlantic war. The Type VIIB in service at the outbreak displaced 753 tons on the surface, made 17.9 knots on the surface and 8 submerged, and could cruise 8,700 nautical miles at 10 knots but only about 90 miles submerged at 4 knots. It had four bow tubes and one stern tube, 14 torpedoes, an 88-mm deck gun and a crew of 44 to 48 (uboat.net, “Type VIIB”). The Type IX was a larger ocean boat of about 1,000 tons with more torpedoes and far greater range.

Germany also had surface raiders at sea before the war began. The pocket battleship Admiral Graf Spee sailed on 21 August 1939 for the South Atlantic, and Deutschland followed about three days later for the North Atlantic, each with a supply ship; the Admiralty did not learn of these movements until much later (Roskill, vol. I, ch. IV). With six 11-inch guns and long-range diesels, a pocket battleship could outgun any cruiser fast enough to catch her.

3 September 1939: Athenia

Germany invaded Poland on 1 September 1939. Britain and France declared war on 3 September; the British ultimatum expired at 1100. That evening the Donaldson Atlantic liner Athenia was steaming west from the North Channel toward Montreal. She had sailed from Glasgow and called at Liverpool on 2 September. Her master was Capt. James Cook. Aboard were 1,418 people: 315 crew and 1,103 passengers, among them 316 American citizens (uboat.net, “Athenia”). Many of the passengers were Canadians and Americans going home ahead of the war, and many were women and children. With war declared she was darkened and steering a zigzag course.

Watching her was U-30, a Type VIIA commanded by Oberleutnant zur See Fritz-Julius Lemp, 26 years old. Lemp’s orders, like those of every U-boat commander, were to make war on merchant shipping according to the prize rules, which required a submarine to stop and search a merchant ship and to see to the safety of its crew before sinking it, and they forbade attacks on passenger liners altogether. Lemp sighted Athenia in the late afternoon and followed her. Seeing a large darkened ship on a zigzag course, he apparently decided that she was an armed merchant cruiser, a legitimate warship target (uboat.net).

At 1939 on 3 September, uboat.net’s record puts the attack (other accounts give 1940), U-30 fired torpedoes from submerged at about 56°44’N, 14°05’W, roughly 250 miles west of Inishtrahull off the north coast of Ireland and south of Rockall. One struck the liner. A second torpedo stuck in its tube, putting the U-boat itself in danger for a time. Survivors later spoke of the U-boat surfacing and shelling the ship. The uboat.net account concludes that this was a misreading: some survivors probably saw a torpedo explode near the U-boat.

Athenia stayed afloat through the night and sank stern first the next morning, about 1000 on 4 September by uboat.net’s record and 1040 by others. The first rescuer on the scene was the Norwegian freighter Knute Nelson, which picked up 449 survivors and landed them at Galway. The Swedish yacht Southern Cross picked up 376 and transferred 236 of them to the American freighter City of Flint, Master Joseph A. Gainard, which carried them to Halifax. The British destroyers Electra and Escort took the rest to Greenock while Fame screened them (uboat.net).

Most of the dead were lost not in the explosion but in the rescue. One lifeboat carrying 52 women and three sailors capsized in the darkness after it came into contact with Knute Nelson‘s propeller; only eight of them survived (uboat.net). Another boat capsized beside a rescuing ship, and passengers were crushed while transferring to the destroyers. In all, uboat.net counts 112 dead, 19 crew and 93 passengers; other accounts give 117, of whom 98 were passengers and 19 crew. Twenty-eight of the dead were American citizens. Among the Canadian dead was ten-year-old Margaret Hayworth of Hamilton, Ontario, who died of her injuries; about 1,000 people met the train that carried her body home.

Lemp made no signal about the attack. He reported it only when U-30 returned to port 23 days later, and the U-boat command then decided that the sinking had to be concealed. The page of U-30‘s war diary for 3 September was replaced with a counterfeit page, and the crew were sworn to secrecy (uboat.net). Raeder decided against a court-martial for Lemp. Hitler’s response was to tighten the rules: U-boats were now forbidden to attack passenger ships at all. Over the following weeks, as the war at sea hardened, those restrictions were loosened again step by step.

The denial

Germany’s public answer was denial. Goebbels’s propaganda ministry claimed the British had sunk their own ship, and about a month later the Nazi party newspaper Völkischer Beobachter accused Churchill himself of arranging the loss to turn neutral opinion, especially American opinion, against Germany. The denial held until Nuremberg. In January 1946, in the case against Raeder, the prosecution read a statement by Doenitz admitting that U-30 had torpedoed Athenia and that the sinking had been covered up, and a former member of U-30‘s crew, Adolf Schmidt, testified that he had been sworn to secrecy.

The Admiralty, for its part, drew the conclusion Germany least wanted. Roskill writes that the sinking, “without warning” and on the day war was declared, convinced the Admiralty that unrestricted submarine warfare had begun, though in fact Hitler had ordered the U-boats to observe international law (Roskill, vol. I, ch. VI). Whatever Lemp intended, the British response was to bring back convoy at once.

The convoys return

The machinery for convoy already existed on paper. As war became likely, the Admiralty took control of all British merchant shipping, exercising it through Naval Control Service staffs in ports around the world, which told masters when to sail and what routes to follow (Roskill, vol. I, ch. IV). Within days of the declaration of war, the convoys began.

East coast convoys between the Thames and the Firth of Forth began on 6 September. On 7 September the first outward ocean convoys sailed: OA convoys from Southend, down the Channel, and OB convoys from Liverpool. Outward ships were escorted only to about 12½ degrees West, where the convoy dispersed and the escorts turned back to meet an inbound convoy. The first homeward convoy, SL 1, sailed from Freetown on 14 September; HX 1 left Halifax on 16 September and the first fast convoy, HXF 1, on the 19th; HG 1 left Gibraltar on 26 September (Roskill, vol. I, ch. VI).

The system had gaps. There were not enough escorts to cover the whole ocean passage, so for most of the way a homeward HX convoy had only an armed merchant cruiser or an old battleship or cruiser with it, protection against a raider but not a submarine. Fast and slow ships sailed alone. But in 1939 the gaps mattered less than they would later: with only 18 boats able to operate beyond about 15 degrees West, and no bases outside Germany, the U-boats did most of their work near the British Isles, where the escorts were.

The results came quickly, and they were decisive. By the end of 1939, Roskill records, 5,756 ships had sailed in British convoys and only four of them had been sunk by submarines. Of the 114 Allied merchant ships of 421,156 tons sunk by U-boats in the first four months of the war, only twelve had been in convoy, and five more were stragglers that had fallen behind a convoy (Roskill, vol. I, ch. VI). The rest were ships sailing alone. The lesson of 1917 had been confirmed within a season.

Canada and the Halifax convoys

Canada declared war on Germany on 10 September 1939, a week after Britain. Its navy was tiny. Veterans Affairs Canada counts six ocean-going ships and 3,500 personnel in the Royal Canadian Navy in 1939 (Veterans Affairs Canada, “The Battle of the Atlantic” fact sheet). The six ships were destroyers. Two of them, HMCS St. Laurent and HMCS Saguenay, took the first Halifax convoy, HX 1, out to sea on 16 September 1939: 18 merchant ships bound for Liverpool, handed over at a rendezvous to the British heavy cruisers Berwick and York for the ocean passage.

Halifax, with the sheltered water of Bedford Basin at its head, became the assembly port for the main North American convoys, with ships coming up from American ports, the Caribbean and the St. Lawrence. Over the war the HX series ran to 377 convoys and more than 17,000 ship arrivals; by one tally 206 ships were lost from it, about one percent, and only 110 of those while in convoy (HX convoy listings). By 1945 the Royal Canadian Navy had grown to 434 commissioned vessels and 95,000 men and women (Veterans Affairs Canada), and Canada’s and Newfoundland’s merchant seamen had lost more than 1,600 dead.

Carriers as hunters: Ark Royal and Courageous

With too few escorts to guard the convoys, the Admiralty tried another way to fight the U-boats in the first weeks: sending aircraft carriers, each with a small destroyer screen, to patrol the Western Approaches and hunt them. The idea was that carrier aircraft could search wide areas and that the carrier could answer distress calls from ships under attack. The cost of the idea showed within two weeks.

On 14 September the new carrier Ark Royal, hunting northwest of Ireland, was attacked by U-39. The torpedoes missed astern, apparently exploding early. The carrier’s escorting destroyers counterattacked and sank U-39, and all 44 of her crew were captured (Roskill, vol. I, ch. VI; uboat.net). She was the first U-boat lost in the war.

Three days later the Navy was not so lucky. On the evening of 17 September the old carrier Courageous, converted in the 1920s from a First World War “large light cruiser,” was patrolling southwest of Ireland with only two destroyers, the other two of her screen having been sent off to help a merchant ship. U-29, commanded by Kapitänleutnant Otto Schuhart, had been stalking her. At about 1950 Schuhart fired three torpedoes at a range of under 3,000 yards. Two hit. Courageous rolled over and sank in about fifteen minutes. Her captain, Capt. W. T. Makeig-Jones, and 518 of her company were lost (Roskill, vol. I, ch. VI). She was the first major British warship lost in the war.

The Admiralty withdrew its fleet carriers from anti-submarine hunting. The deeper lesson was that searching the open ocean for U-boats wasted ships and invited disaster: the place to fight submarines was around the convoys, because that was where the submarines had to come.

Meanwhile the U-boats already at sea were running short of fuel and torpedoes. On 7 September, Roskill writes, 21 ocean-going boats were on patrol; by 18 September only eleven remained in the Atlantic (Roskill, vol. I, ch. VI). The first group attack on a convoy, by U-31 on OB 4 on 16 September, sank a single ship. The fight against convoy, which Doenitz had trained for, was beyond the means of the force he had.

Scapa Flow: U-47 and the Royal Oak

Scapa Flow, the great natural anchorage enclosed by the Orkney Islands off the north tip of Scotland, had been the Grand Fleet’s base in the First World War and was again the base of the Home Fleet. In the First World War two U-boats had tried to get in and both had been lost. Its eastern entrances, the narrow sounds between the small islands on its eastern side, had been blocked with sunken ships, but the blockships had shifted over twenty years and the gaps had not all been closed. German aerial reconnaissance and Doenitz’s staff had studied the entrances. Doenitz chose Kapitänleutnant Günther Prien of U-47, a Type VIIB, for the attempt.

U-47 sailed from Kiel and approached the Orkneys on the night of 13–14 October 1939, a night chosen for its high tide and lack of moon. Prien came in from the east through Kirk Sound, north of the small island of Lamb Holm. He passed between the blockships Seriano and Numidian, briefly touched bottom and fouled a cable strung from Seriano, and was through into the Flow at about 0027 on 14 October. Most of the Home Fleet was away. Prien found the battleship Royal Oak, flagship of the Second Battle Squadron, lying at anchor in the northeast corner of the Flow, under the cliffs near Scapa Bay, where she had been placed to help defend the base against air attack.

Prien fired a salvo of three torpedoes from his bow tubes at about 0058. Two missed. One struck Royal Oak at her bow at about 0104, doing little visible damage. Aboard the battleship the explosion was taken for an internal blast, perhaps in a storeroom, and most of the crew did not go to action stations. Prien turned, reloaded, and at about 0116 fired a second salvo of three torpedoes. These struck Royal Oak amidships. Fires and explosions tore through the ship. She rolled over and sank at about 0129, thirteen minutes after the second hit. The times are those usually given in published accounts and are approximate. U-47 went out the way she had come and was back in Wilhelmshaven three days later.

Royal Oak had 1,234 men and boys aboard. Of them, 835 died that night or later of their wounds, according to the count settled in 2019; for decades the figure was given as 833 or 834. Among the dead were Rear Adm. Henry Blagrove, commanding the Second Battle Squadron, and 134 boy seamen under 18. Many survivors owed their lives to the drifter Daisy II, tied up alongside, whose skipper, John Gatt, cut her loose as the battleship heeled and spent the next two and a half hours pulling 386 men from the oily water. Gatt received the Distinguished Service Cross.

Prien came home a national hero. Hitler received him in Berlin and awarded him the Knight’s Cross of the Iron Cross, the first given to a U-boat officer; every member of his crew received the Iron Cross Second Class. German propaganda called him “the Bull of Scapa Flow.” Doenitz was promoted to rear admiral, with effect from 1 October, and his title had already changed in September from FdU to Befehlshaber der Unterseeboote (BdU), Commander U-boats (uboat.net).

For the British the sinking was a humiliation and a warning. The Home Fleet left Scapa Flow for less exposed anchorages on the west coast of Scotland while the defenses were rebuilt. Churchill ordered the eastern sounds sealed for good with causeways of concrete blocks across Kirk Sound, Skerry Sound, Weddel Sound and Water Sound, linking Lamb Holm, Glimps Holm, Burray and South Ronaldsay to the Orkney mainland. The Churchill Barriers, built largely by Italian prisoners of war, were essentially finished by September 1944 and formally opened just after the German surrender in May 1945.

The magnetic mine

In the autumn of 1939 the most dangerous German weapon against British shipping was not the torpedo but the mine. German destroyers, U-boats and aircraft laid mines in the approaches to British ports and along the east coast. Many were of a new kind that lay on the bottom in shallow water and were fired by a ship’s own magnetism, which a sensitive needle in the mine detected as the steel hull passed overhead. A ship did not have to touch such a mine, and the wire sweeps used against moored mines could not clear it.

The losses mounted fast. By Roskill’s count, mines sank 19 merchant ships of 59,027 tons by the end of October, 27 ships of 120,958 tons in November, and 33 ships of 82,712 tons in December, together with the destroyer Blanche. Over the first four months of the war mines sank 79 merchant ships of 262,697 tons, and in the last two months of 1939 they overtook the U-boats as the main cause of British losses (Roskill, vol. I, ch. VI). Among the victims was the Dutch liner Simon Bolivar, a neutral ship, mined off the east coast on 18 November with heavy loss of life.

The answer depended on getting a mine intact. On the night of 22–23 November a German aircraft dropped one by parachute onto the mudflats off Shoeburyness, at the mouth of the Thames, where it lay exposed at low tide. On 23 November two officers of HMS Vernon, the Navy’s mine school at Portsmouth, Lt. Cmdr. John Ouvry and Lt. Cmdr. Roger Lewis, went out to it with Chief Petty Officer Baldwin and Able Seaman Vearncombe. Using non-magnetic tools, Ouvry took it apart “at great personal risk,” in Roskill’s words, while the others recorded each step so that, if he were killed, the next man would know what not to do.

The mine, Roskill writes, was fired by a change in the vertical magnetic field produced by a ship built in the northern hemisphere. Knowing that, the scientists could defeat it. A special department was set up to “degauss” ships by fitting electric cables around their hulls to cancel their magnetism, an effort Roskill compares to the arming of the Merchant Navy (Roskill, vol. I, ch. VI), and new sweeps were developed to set the mines off at a safe distance. By early 1940 the magnetic mine had been brought under control.

Distinguished Service Order

Lt. Cmdr. John G. D. Ouvry and Lt. Cmdr. Roger C. Lewis, HMS Vernon

Both officers received the DSO, gazetted on 23 December 1939, for “great courage and skill in securing and stripping live enemy mines without regard for own safety.” King George VI presented the awards himself at HMS Vernon on 19 December 1939. Chief Petty Officer Baldwin and Able Seaman Vearncombe, who assisted at Shoeburyness, were also decorated. The George Cross, later the usual award for this kind of work, did not yet exist; it was instituted in September 1940.

MCDOA awards record →

Raiders: Rawalpindi, the pocket battleships and the River Plate

The German Navy’s surface ships were the other threat to the convoys in 1939. The convoy system gave no protection against a pocket battleship or battlecruiser, which could destroy the escorts and then the merchant ships. That was why HX convoys were given cruisers and old battleships for the ocean passage, and why the Admiralty, on 5 October, formed eight hunting groups, lettered F through N, of carriers, battlecruisers and cruisers, to search for the raiders in the Atlantic and Indian Oceans (Roskill, vol. I, ch. VII).

Deutschland had a frustrating cruise in the North Atlantic. She sank only two ships, Stonegate and the Norwegian Lorentz W. Hansen, and seized the American freighter City of Flint, the ship that had carried Athenia‘s survivors to Halifax, as a prize for carrying contraband; a German prize crew took her to Murmansk, where she arrived on 22 October. Deutschland was recalled on 1 November and reached Kiel on 15 November (Roskill, vol. I, ch. VII).

Late in November the battlecruisers Scharnhorst and Gneisenau made a sortie into the Iceland–Faroes gap. On 23 November they came upon the armed merchant cruiser Rawalpindi, a P&O liner armed with old 6-inch guns, on the Northern Patrol southeast of Iceland at about 63°40’N, 12°31’W. Her captain, Capt. Edward Coverley Kennedy, a retired officer recalled for the war, chose to fight rather than surrender. Rawalpindi was destroyed in minutes. uboat.net gives 275 killed, Kennedy among them; the German ships picked up 27 survivors, and a few more were rescued later.

In the South Atlantic, Admiral Graf Spee under Capt. Hans Langsdorff had a longer run. Between 26 September and 13 December she sank nine merchant ships of about 50,000 tons, moving between the shipping lanes off Brazil and the Cape of Good Hope and once into the Indian Ocean, and handing her prisoners over to her supply ship Altmark (Roskill, vol. I, ch. VII). Langsdorff was careful to take crews off before sinking their ships; none of the men in the ships she sank was killed. But the raider tied up a large part of the Royal Navy’s cruiser strength in the search.

Commodore Henry Harwood, commanding the South America Division, guessed that Langsdorff would be drawn to the rich shipping off the River Plate, the estuary between Uruguay and Argentina, and concentrated his three available cruisers there: the heavy cruiser Exeter, with 8-inch guns, and the light cruisers Ajax, his flagship, and Achilles, a New Zealand-manned ship, with 6-inch guns. On the morning of 13 December 1939, Graf Spee came over the horizon. Smoke was sighted at about 0610, and the German ship opened fire at about 0618 at a range of about 19,000 yards.

Harwood split his force so that Graf Spee would have to divide her fire, with Exeter attacking from one side and the two light cruisers from the other. Exeter took the worst of it: hit repeatedly by 11-inch shells, she lost most of her armament and was left burning and listing. Ajax lost both her after turrets and her topmast. But the cruisers hit Graf Spee repeatedly, and at about 0740 Langsdorff broke off the action and steered for the neutral port of Montevideo, with the two light cruisers shadowing him (Roskill, vol. I, ch. VII). The British lost 72 men killed: 61 in Exeter, seven in Ajax and four in Achilles. Graf Spee lost 36 killed and about 60 wounded.

At Montevideo the Uruguayan government gave Langsdorff seventy-two hours to make his ship seaworthy. British diplomats encouraged reports that a powerful force, including Ark Royal and Renown, was waiting offshore; in fact only the cruiser Cumberland had joined Harwood’s two damaged light cruisers. Langsdorff, believing his ship could neither fight her way out nor reach Germany, decided to scuttle her. At 1815 on 17 December Graf Spee sailed down the river with a skeleton crew, and at 1956 she blew herself up (Roskill, vol. I, ch. VII). Langsdorff took his crew to Buenos Aires, where on the night of 19–20 December he shot himself.

Harwood was promoted to rear admiral and knighted. The battle was the first British naval victory of the war, and it came at a moment when there was little else to celebrate. Its importance for the Atlantic was that it ended the pocket battleship threat for the time being. In February 1940 the destroyer Cossack boarded Altmark in a Norwegian fjord and freed some 300 British merchant seamen taken from Graf Spee‘s victims, an incident that helped persuade Hitler to invade Norway.

The first winter

By the end of 1939 the U-boats had done real damage, mostly to ships sailing alone, and the mines nearly as much. The cost to Germany was heavy for so small a force. Nine U-boats were lost in 1939: U-39 and U-27 to destroyers in September; U-12, U-40 and U-16 to mines; U-42 and U-45 to escorts in October; U-35 in November and U-36 in December (uboat.net, “U-boat losses 1939”). Roskill calls that “about one-sixth” of the U-boat strength (Roskill, vol. I, ch. VI).

By the numbers

Shipping lost by cause, September 1939 to March 1940

British, Allied and neutral merchant ships, all areas, thousands of gross tons

Submarines765 (222 ships)

Mines430 (129 ships)

Surface warships63 (16 ships)

Aircraft37 (30 ships)

Other causes8 (5 ships)

Across the Atlantic the United States stayed out but not untouched. On 3 October 1939 the American republics, meeting at Panama, declared a neutrality zone off their coasts. On 4 November the Neutrality Act was amended to let Britain and France buy American arms on a “cash and carry” basis, while American ships were barred from the war zones around Europe. Everything Britain bought in America would cross the ocean in British and Allied hulls, under the convoy system now being built.

Timeline

The opening of the Atlantic war, 1939–1940

1. 21–24 Aug 1939Admiral Graf Spee and then Deutschland sail for their Atlantic waiting areas.
2. 31 Aug 193939 U-boats are in or on their way to positions around the British Isles.
3. 1 Sep 1939Germany invades Poland.
4. 3 Sep 1939Britain and France declare war. At about 1939, U-30 (Lemp) torpedoes Athenia; she sinks the next morning.
5. 6–7 Sep 1939East coast convoys begin; the first OA and OB convoys sail outward.
6. 10 Sep 1939Canada declares war on Germany.
7. 14 Sep 1939U-39 misses Ark Royal and is sunk, the first U-boat lost. The first SL convoy sails from Freetown.
8. 16 Sep 1939HX 1 sails from Halifax with 18 ships, escorted out by HMCS St. Laurent and Saguenay. U-31 attacks OB 4.
9. 17 Sep 1939U-29 (Schuhart) sinks Courageous; 519 lost.
10. 5 Oct 1939The Admiralty forms eight hunting groups against the surface raiders.
11. 14 Oct 1939U-47 (Prien) sinks Royal Oak in Scapa Flow; 835 lost.
12. 4 Nov 1939U.S. Neutrality Act amended to permit “cash and carry.”
13. 23 Nov 1939Scharnhorst sinks Rawalpindi. Ouvry and Lewis strip the first magnetic mine at Shoeburyness.
14. 13 Dec 1939Battle of the River Plate.
15. 17 Dec 1939Graf Spee scuttled off Montevideo.
16. 16 Feb 1940HMS Cossack frees British prisoners from Altmark in Norwegian waters.
17. 9 Apr 1940Germany invades Denmark and Norway; U-boats are withdrawn from the Atlantic to support the landings.
18. 15 Apr 1940U-47 fires eight torpedoes at British transports near Narvik; none hits.
19. 8 Jun 1940The last Allied troops leave Narvik.

Norway and the torpedo crisis

In March 1940 Doenitz was ordered to pull his U-boats out of the Atlantic. Germany was preparing to invade Denmark and Norway, and the U-boats were to support the landings by attacking the British warships and transports that would come to Norway’s aid. The invasion began on 9 April 1940. About 30 U-boats were positioned along the Norwegian coast and in the waters between Norway and the Orkneys, organized in eight groups (uboat.net, “The Norwegian Operation and the Torpedo Crisis”). It was nearly the whole operational force, and the Atlantic convoys were left almost untouched for two months.

On paper it was an ideal opportunity: British warships and troopships crowding into narrow fjords where U-boats were waiting. In practice commanders made textbook attacks and watched their torpedoes run under the target, explode early, or not explode at all. Herbert Schultze in U-48 attacked the battleship Warspite without result on 14 April. Late on 15 April Prien found three large British transports and several smaller ships at anchor in Bygdenfjord, north of Narvik, disembarking troops, and fired eight torpedoes with contact pistols at stationary targets. None hit. On 19 April two more fired at Warspite failed (uboat.net, “The Norwegian Operation”). Prien told Doenitz he could hardly be expected to fight with a dummy rifle.

The faults compounded each other. A German torpedo could be fitted with a contact pistol or a magnetic pistol, meant to fire under the target’s keel. In northern Norwegian waters the magnetic pistols fired early or not at all, so commanders were ordered to use contact pistols. But the electric G7e torpedo also had a defective depth-keeping mechanism and ran about six feet deeper than set, passing under its target. The cause, traced only in January 1942, was a leaking balance chamber in the depth gear: air pressure that built up inside a long-submerged U-boat leaked into it and threw off its setting (uboat.net). The failure rate in the Norwegian campaign was finally put at 30 to 35 percent of attacks.

Doenitz concluded that the torpedoes “refused to function in northern waters” with either kind of pistol. His commanders’ confidence in their weapon collapsed. A commission of inquiry, set up in mid-April, reported in late July 1940 and laid much of the blame on the Torpedo Department; officials of the Torpedo Experimental Institute were court-martialed and sentenced to prison (uboat.net). The depth fault was not fully cured until 1942, and a reliable magnetic pistol with a contact backup came only in December 1942. For the British, the torpedo failures in Norway were a piece of luck whose size they did not appreciate at the time. How many warships and troopships survived the campaign because of it can only be guessed.

The Norwegian campaign ended in early June with the Allied withdrawal from Narvik. By then France was collapsing; it signed an armistice on 22 June. The U-boat arm came out of Norway no larger than it had gone to war, with about 25 operational boats and never more than 15 at sea at once (naval-history.net). But Germany now held the coast of Europe from the North Cape to Spain, and Doenitz could move his boats to the Biscay ports of France, hundreds of miles closer to the convoy routes. What followed, the U-boat aces’ “happy time” and the destruction of convoy SC 7, is told in Chapter 2.

People

Karl Doenitz (1891–1980) led Germany’s U-boats from 1 January 1936, as FdU and from September 1939 as BdU. He devised the wolf-pack tactics and trained the crews. He became a rear admiral on 1 October 1939, and grand admiral and commander-in-chief of the Navy at the end of January 1943, keeping command of the U-boats. Both his sons died at sea. Hitler named him his successor, and he was briefly head of state in May 1945. Sentenced at Nuremberg to ten years’ imprisonment, he was released in 1956.

Fritz-Julius Lemp (1913–1941) commanded U-30 when he sank Athenia. He was later given U-110, and on 9 May 1941 he was killed when his boat was forced to the surface by British escorts in the North Atlantic. The British boarded U-110 and recovered her Enigma machine and code material before she sank, a story told in Chapter 3 and Chapter 5.

Günther Prien (1908–1941), a former merchant marine officer, commanded U-47 from 1938. After Scapa Flow he became one of the leading U-boat aces of 1940. U-47 was lost with all hands while attacking convoy OB 293 in March 1941; the cause has never been settled with certainty.

Otto Schuhart commanded U-29 when she sank Courageous, the first major British warship lost in the war. He survived the war.

Capt. James Cook was master of Athenia. He supervised the abandonment of his ship in darkness, and nearly all of the deaths came in the boats and during the rescue rather than in the ship.

Commodore Henry Harwood (1888–1950) commanded the British cruisers at the River Plate. His tactics of dividing his force and pressing the attack despite the damage to Exeter drove Graf Spee into Montevideo. He was promoted to rear admiral and knighted, and later commanded in the Mediterranean.

Capt. Hans Langsdorff (1894–1939) commanded Admiral Graf Spee. He sank nine ships without killing any of their crews, and after the River Plate chose to scuttle his ship rather than lead his men into what he believed was a hopeless fight. He took his own life in Buenos Aires on the night of 19–20 December 1939.

Lt. Cmdr. John Ouvry of HMS Vernon stripped the first German magnetic mine at Shoeburyness on 23 November 1939. The information he recovered made degaussing possible.

Capt. Edward Coverley Kennedy (1879–1939), a retired officer recalled to command the armed merchant cruiser Rawalpindi, fought two battlecruisers on 23 November 1939 and was killed with most of his crew. His son, the broadcaster Ludovic Kennedy, later served in the destroyer Tartar in the hunt for the Bismarck.

Losses and uncertainty

The numbers for the first months of the battle look precise, but most of them come in more than one version. The table gathers the main ones.

The Athenia figures differ for familiar reasons. Some counts include people who died after reaching shore and some do not; some separate passengers who died in the capsized boats from those killed in the ship. The Commonwealth War Graves Commission’s figure is lower because it records only British Commonwealth civilian dead. The number of Canadians lost is the least settled figure, and the sources we found disagree widely.

The shipping loss totals vary even more, because they count different things. Roskill’s 114 Allied ships of 421,156 tons sunk by U-boats in September–December 1939 counts British and Allied ships only. The naval-history.net summary counts neutrals too, and reaches 222 ships sunk by submarines in the seven months to March 1940. uboat.net’s monthly tables count every ship hit by a U-boat, including damaged and captured ships: 52 in September 1939, 37 in October, 30 in November and 46 in December. Before comparing figures, check whether neutral ships, damaged ships, and losses to mines and aircraft are included.

Even the size of the U-boat arm at the outbreak is given two ways: Roskill counts 56 completed boats, most other sources 57. The British Director of Naval Intelligence, two days into the war, estimated 30 coastal and 29 ocean-going boats, three more than the actual total. On the nine U-boats lost in 1939, British and German records agree.

Questions readers ask

Did Germany mean to sink the Athenia?

No. U-boat commanders had orders to follow the prize rules and to leave passenger liners alone. Lemp seems to have taken the darkened, zigzagging liner for an armed merchant cruiser. The German government then denied any responsibility, and blamed Churchill, until Doenitz admitted the truth in a statement read at Nuremberg in January 1946.

Why did Britain bring back convoys so quickly?

Because convoy had defeated the U-boats in 1917 and 1918, and the Admiralty had plans ready. The Athenia sinking convinced it that unrestricted submarine warfare had begun. Outward convoys sailed on 7 September and the first Halifax convoy on 16 September. By the end of 1939 only four of 5,756 ships sailing in convoy had been sunk by submarines.

How did U-47 get into Scapa Flow?

Through Kirk Sound, one of the narrow eastern entrances, on a dark night at high tide. The sound had been blocked with sunken ships, but they had shifted and left a gap. Prien squeezed between the blockships Seriano and Numidian, touched bottom, and got through. The Churchill Barriers now close all four eastern sounds.

Was ASDIC useless?

No, but it was oversold. It could find a submerged U-boat at moderate range in good conditions with a trained operator, and it was the basis of every British anti-submarine attack. But it could not find a U-boat on the surface, it lost contact at close range just before an attack, and there were far too few escorts carrying it. The Navy’s faith in it led to too few escorts being built before the war.

Why didn’t Germany have more U-boats in 1939?

Because the Navy’s building plan, the Z Plan, put battleships first and assumed war would not come before the mid-1940s. Doenitz wanted 300 ocean-going boats. He went to war with 56 or 57, of which only about 46 were ready for operations and only 26 or 27 could reach the Atlantic. That gap did not close until 1941 and 1942.

What went wrong with the German torpedoes in Norway?

Two separate faults. The magnetic pistols fired early or not at all in northern waters, and the torpedoes’ depth mechanism let them run about six feet deeper than set, so that contact-fired torpedoes passed under their targets. Some 30 to 35 percent of attacks failed. The depth fault was not traced until January 1942.

How it connects

This is the first chapter of the Battle of the Atlantic collection. The fall of France, the Biscay bases, the first wolf packs and convoy SC 7 follow in Chapter 2, The Happy Time. Lemp’s death in U-110, the Reuben James and the Bismarck are in Chapter 3; the U-boat offensive off North Carolina is Chapter 4; ASDIC’s successors, radar and direction finding, and the code war are in Chapter 5. The Pearl Harbor collection covers the attack that brought the United States into the war, and the Battle of the Atlantic FAQ answers common questions about the whole campaign.

What happened afterward

The convoy system built in September 1939 lasted, with constant change, until the end of the war. The OA series ended in 1940 when the Channel became too dangerous; the OB convoys were replaced in 1941 by ON convoys escorted all the way across. The HX series ran from Halifax until 1942 and then from New York, and the last HX convoys sailed in 1945. The Royal Canadian Navy took over a large share of the escort work in the North Atlantic, and Halifax remained the great Canadian convoy port to the end.

Lemp and Prien were dead by the spring of 1941; Doenitz rose to command the German Navy and, briefly, the German state. Ark Royal was sunk by U-81 in the Mediterranean in November 1941, and Exeter by the Japanese in the Java Sea in March 1942. Parts of Graf Spee‘s wreck off Montevideo, including a rangefinder and the ship’s eagle, have been raised. In 2017 the shipwreck hunter David Mearns said he was “98 per cent” sure he had found Athenia, broken in two in about 650 feet of water some 50 miles south of Rockall, though no image of her name had yet confirmed it (Royal Navy news, 6 October 2017).

At Scapa Flow, Royal Oak lies almost upside down in about 100 feet of water, a designated war grave protected by the Protection of Military Remains Act 1986. Each year Royal Navy divers place a White Ensign on her stern. Twenty-six of her dead, eight of them unidentified, were buried in the naval cemetery at Lyness on the island of Hoy.

Walking the ground today

Orkney. The Royal Oak memorial in St Magnus Cathedral, Kirkwall, has a plaque, a book of remembrance and the ship’s bell. A buoy marks the wreck in Scapa Bay; diving on it is prohibited. The Churchill Barriers carry the road across Lamb Holm, Glimps Holm and Burray to South Ronaldsay, with blockship remains still visible beside them, and on Lamb Holm stands the Italian Chapel built by the prisoners who worked on them. The Scapa Flow Museum at Lyness on Hoy displays the brass name letters from Royal Oak‘s stern, and the naval cemetery is nearby.

Liverpool. The Western Approaches headquarters at Derby House, from which the convoy battle was directed after February 1941, is preserved as a museum. The Merseyside Maritime Museum has galleries on the Battle of the Atlantic and the merchant navy.

Halifax. The Maritime Museum of the Atlantic on the Halifax waterfront covers the convoy port, and in summer the corvette HMCS Sackville, the last surviving Flower-class corvette and Canada’s Naval Memorial, is open to visitors nearby. Point Pleasant Park and the shore of Bedford Basin overlook the waters where the convoys assembled.

Montevideo. Artifacts from Graf Spee, including her anchor and a rangefinder raised from the wreck, are displayed in the port area of Montevideo.

North Carolina. The U-boats of 1939 could not reach American waters, but within three years their successors were sinking ships in sight of the Outer Banks. The Graveyard of the Atlantic Museum in Hatteras tells that story; NOAA’s Monitor National Marine Sanctuary manages the “Battle of the Atlantic” wreck sites offshore; and the British Cemetery on Ocracoke holds men of the armed trawler Bedfordshire. See Chapter 4 and Chapter 9, and check opening hours and access rules before visiting any of these sites.

Sources and further reading

• Stephen W. Roskill, The War at Sea, 1939–1945, vol. I, The Defensive (HMSO, 1954): ch. IV, Allied and Enemy War Plans and Dispositions; ch. VI, The Sea Approaches and Coastal Waters (Sept–Dec 1939); ch. VII, Ocean Warfare (Sept–Dec 1939) (HyperWar texts).
• W. K. Hancock and M. M. Gowing, British War Economy (HMSO, 1949): ch. X, War Transport and ch. XIV, Outline of Shipping (HyperWar texts).
• uboat.net: “Athenia”; “ASDIC”; “Type VIIB”; “Befehlshaber der Unterseeboote (BdU)”; “U-boat losses 1939”; “The Norwegian Operation and the Torpedo Crisis”; “HMS Rawalpindi”; “Ships hit by U-boats, by month.”
• naval-history.net, “Battle of the Atlantic” (monthly summaries and losses by cause, September 1939–June 1940, after the official histories).
• Encyclopedia 1914–1918 Online, “Atlantic U-Boat Campaign” (losses of April 1917 and the introduction of convoy).
• Veterans Affairs Canada, “The Battle of the Atlantic” fact sheet (RCN strength 1939 and 1945, Canadian losses); Valour Canada, “SS Athenia Sunk.”
• Minewarfare and Clearance Diving Officers’ Association, WWII awards records for Ouvry and Lewis.
• Royal Navy news, “Sunk by U-boats: wreck of liner Athenia discovered” (6 October 2017).
• For the Nuremberg admission on Athenia: Trial of the Major War Criminals before the International Military Tribunal, proceedings of January 1946 (Harvard Law School Nuremberg Trials Project).
• For the wider story: Clay Blair, Hitler’s U-Boat War: The Hunters, 1939–1942 (1996); Samuel Eliot Morison, The Battle of the Atlantic, September 1939–May 1943 (History of United States Naval Operations in World War II, vol. I, 1947); Marc Milner, Battle of the Atlantic (2003) and North Atlantic Run (1985); F. H. Hinsley, British Intelligence in the Second World War, vol. I (1979); Jürgen Rohwer, Chronology of the War at Sea; Karl Doenitz, Memoirs: Ten Years and Twenty Days (1959); Imperial War Museums, Battle of the Atlantic collections.

Photographs: Imperial War Museums (Royal Navy official and press agency photographs, public domain), Royal Navy, Canada Department of National Defence, and the German Federal Archives (Bundesarchiv, CC BY-SA 3.0 DE), via Wikimedia Commons.