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September 1939 - March 1940

HMS Hermes, aircraft carrier  (Navy Photos, click to enlarge)

on to April-May 1940


Battle of the River Plate (see December 1939)





3rd - After Germany invaded Poland on the 1st, Britain and France demanded the withdrawal of German forces. The ultimatum expired and at 11.15am on the 3rd, Prime Minister Neville Chamberlain broadcast to announce that Britain was at war with Germany. He formed a War Cabinet with Winston Churchill as First Lord of the Admiralty. France, Australia, New Zealand and India (through the Viceroy) declared war the same day. 6th - South Africa declared war. 10th - Canada declared war.


Battle of the Atlantic - The six-year long Battle started on the 3rd with the sinking of liner "Athenia" by "U-30" (Lt Lemp) northwest of Ireland. She was mistaken for an armed merchant cruiser, and her destruction led the Admiralty to believe unrestricted submarine warfare had been launched. Full convoy plans were put into operation, but in fact Hitler had ordered the U-boats to adhere to international law and after the "Athenia" incident, tightened controls for a while. Liverpool-out convoy OB4 was the first group of ships to be attacked, with "U-31" sinking one ship on the 16th September. Convoys actually suffered little harm over the next seven months, and most of the losses due to U-boats were among the independently routed and neutral merchantmen. In the period to March 1940 they sank 222 British, Allied and neutral ships in the Western Approaches to the British Isles, the North Sea and around the coasts of Britain. In the same time they lost 18 of their number, a third of all in commission in September 1939 and more than the number of new boats entering service.

14th - After an unsuccessful attack on carrier Ark Royal off the Hebrides, NW Scotland, German "U-39" was depth-charged and sunk by screening destroyers "Faulknor", "Firedrake" and "Foxhound". 17th - Three days later, fleet carrier COURAGEOUS was sent to the bottom to the southwest of Ireland by "U-29" with heavy loss of life. Carriers were withdrawn from anti-U-boat patrols as it became accepted that the best chance of sinking U-boats was to attract them to well-defended convoys where the escorts could hunt them down. 20th - After sinking trawlers off the northern Hebrides, German "U-27" was located and sunk by destroyers "Fortune" and "Forester".

German Heavy Warships - Pocket battleship "Admiral Graf Spee" sank her first ship in the Atlantic off Brazil on the 30th September.

Monthly Loss Summary: 20 British, Allied and neutral ships of 110,000 tons in the Atlantic from all causes; 1 fleet carrier; 2 German U-boats.


Western Front - Advance units of the British Expeditionary Force were carried by destroyers from Portsmouth to Cherbourg on the 4th September. A week later the main force started landing in France. By June 1940 half a million men had been carried in both directions without loss.

German Codes - The British Code & Cipher School moved to Bletchley Park, England, the site of its magnificent successes breaking the German Enigma codes through the 'Ultra' programme. The School built on the work of Polish and later French code-breakers. By April 1940 the first low level Luftwaffe codes were being deciphered. Many months followed before comparable progress was made with Naval codes.

4th - Aircraft of RAF Bomber Command made their first attack on German warships in Wilhelmshaven and Brunsbuttel. Cruiser "Emden" was slightly damaged by a crashing aircraft.

10th - Home Fleet submarines on patrol off southwest Norway suffered their first casualty in tragic circumstances. OXLEY was torpedoed in error by "Triton" and went down off Obrestad.

Polish Campaign - As the Germans advanced into Poland, Russia invaded from the east on the 17th September. Warsaw surrendered to the German Army on the 28th and next day the country was partitioned in accordance with the Soviet-German Pact.

Monthly Loss Summary: 33 British, Allied and neutral ships of 85,000 tons in UK waters.




Americas - The Pan-American Conference established a 300-mile plus security zone off the coasts of the Americas within which all hostile action by the belligerent powers was forbidden.

German Heavy Warships - Pocket battleship "Graf Spee" claimed four more merchant ships in the South Atlantic before heading into the southern Indian Ocean. Seven Allied hunting groups were formed in the Atlantic and one in the Indian Ocean to search for her. In total the Royal and French Navies deployed three capital ships, four aircraft carriers and 16 cruisers. Meanwhile sister ship "Deutschland", after accounting for two ships in the North Atlantic was ordered home. She reached Germany in November and was renamed "Lutzow".

13th - Two U-boats attacking convoys to the southwest of Ireland were sunk by escorting destroyers. On the 13th, "U-42" was sent to the bottom by "Imogen" and "llex" sailing with Liverpool-out convoy OB17. 14th - Next day "Icarus", "Inglefield", "Intrepid" and "Ivanhoe" escorting Kingston, Jamaica/UK convoy KJ3 accounted for "U-45"

Battle of the Atlantic - The first UK/Gibraltar convoy, OG1, sailed in October. Partly because of the loss of "U-42" and "U-45", only three of the intended nine U-boats were available for the first U-boat group attack on a convoy using an on-board tactical commander. Three ships out of the 27 in unescorted convoy HG3 were sunk, but the experiment was repeated only a few times. The first wolf-pack attacks conducted personally by Adm Doenitz from onshore did not start for another year.

Monthly Loss Summary: 22 British, Allied and neutral ships of 133,000 tons in the Atlantic from all causes; 2 German U-boats.


Polish Campaign, Conclusion - With Poland partitioned between Germany and Russian, the last of the Polish Army surrendered on 5th October. Poland entered its long dark years of brutality and oppression.

Western Front - Most of the British Expeditionary Force was now in France, just as Hitler ordered preparation of the first plans for the invasion of France and the Low Countries.

German Heavy Warships - Battlecruiser "Gneisenau" and other ships of the German Navy sortied on the 8th off Norway to draw the Home Fleet within U-boat and aircraft range. Capital ships Hood, Nelson, Repulse, Rodney and Royal Oak together with carrier Furious, cruisers and destroyers sailed for various positions, but no contact was made.

8th - The anti-U-boat mine barrage in the Strait of Dover was completed and accounted for three U-boats, starting with "U-12" on the 8th. 13th - "U-40" was mined. 24th - The third U-boat was "U-16". No more attempts were made to pass through the English Channel and U-boats were forced to sail around the north of Scotland to reach the Atlantic.

14th - Returning to Scapa Flow after guarding the Fair Isle passage during "Gneisenau's" recent sortie, anchored battleship ROYAL OAK  (right - Maritime Quest) was torpedoed and sunk by "U-47" (Lt-Cdr Prien) in the early hours of the 14th with the loss of 833 men. The Home Fleet moved to Loch Ewe on the W Scottish coast

German Sea and Air Attacks - These were stepped up against merchant shipping and warships in British waters. In their first attack on British territory, Ju.88's bombed ships in the Firth of Forth, Scotland on the 16th October and slightly damaged cruisers SouthamptonEdinburgh and destroyer "Mohawk". Next day more Ju.88's struck at Scapa Flow and the old gunnery training battleship Iron Duke was bomb-damaged and had to be beached. German destroyers and later other surface vessels started laying mines off the British East Coast. Aircraft also attacked the East Coast convoy routes, but initially without success. In defence, it took some months for RAF Fighter Command to arrange effective sweeps, but there were too few AA guns to arm merchantmen.

Monthly Loss Summary: 24 British, Allied and neutral ships of 63,000 tons in UK waters; 3 German U-boats




United States - The Neutrality Act was amended to allow the supply of arms to belligerents on a 'cash and carry' basis. At the same time American shipping was banned from the war zones.

German Heavy Warships - Pocket battleship "Graf Spee" sank a small tanker southwest of Madagascar and headed back for the South Atlantic. More Allied hunting groups were formed.

23rd - Armed merchant cruiser "RAWALPINDI" (Capt E. C Kennedy) on Northern Patrol was sunk by the 11in battlecruiser "Scharnhorst" as she and sister ship "Gneisenau" tried to break out into the Atlantic. After the action to the southwest of Iceland, they turned back and returned to Germany after avoiding searching ships of the British Home Fleet.

29th - On patrol to the north of Scotland to support the German battlecruiser's attempted breakout, "U-35" was found east of the Shetland Islands and sunk by destroyers "Kashmir", "Kingston" and "Icarus".

Battle of the Atlantic - RAF Coastal Command continued to patrol for U-boats on passage into the Atlantic. Equal priority was now given to attacks, but the crews were not trained and lacked effective anti-submarine bombs. The first success was a joint action with the Royal Navy at the end of January 1940.

Monthly Loss Summary: 6 British, Allied and neutral ships of 18,000 tons in the Atlantic from all causes, 1 armed merchant cruiser; 1 German U-boat.


13th - As U-boat and surface ship-laid mines continued to inflict heavy losses on merchant ships and warships alike, cruiser minelayer Adventure and accompanying destroyer BLANCHE were mined in the Thames Estuary. "Blanche" was a total loss. More serious casualties followed a week later. 21st - Recently completed light cruiser Belfast was badly damaged in the Firth of Forth on a magnetic mine laid by "U-21". With her back broken and machinery mountings shattered she was out of action for three years. 21st - Destroyer GIPSY was also lost on mines laid by destroyers off the British east coast port of Harwich.

20th - British Home Fleet submarines gained their first success in the Heligoland Bight when "Sturgeon" sank German patrol ship "V-209".

Magnetic Mines - German seaplanes also laid the first magnetic mines off the East Coast and dropped one on tidal flats at Shoeburyness in the Thames Estuary. It was defused on the 23rd November and recovered by Lt-Cdr Ouvry, a vital step in the battle against a weapon which was causing heavy losses and long shipping delays. In November alone, 27 ships of 121,000 tons were sunk and for a time the Thames Estuary was virtually closed to shipping.

Russo-Finnish War - Negotiations on border changes and control of islands in the Gulf of Finland broke down and Russia invaded on the 30th. Fiercely resisted by the small Finnish army, the war dragged on to March 1940

Merchant Shipping War - The first HN/ON convoys sailed between the Firth of Forth and Norway in November covered by the Home Fleet. The convoys were discontinued in April 1940.

Monthly Loss Summary: 43 British, Allied and neutral ships of 156,000 tons in UK waters.




Canada - The first Canadian troop convoy TC1, sailed from Halifax, Nova Scotia for Britain, heavily escorted and accompanied part of the way by Canadian destroyers.

13th, Battle of River Plate (see map above) - Now back in the South Atlantic, “Graf Spee” (right - Maritime Quest)claimed three more victims to bring the total to nine ships of 50,000 tons, before heading for the South American shipping lanes off the River Plate. Cdre Harwood with Hunting Group G - 8in-gunned cruisers Exeter and Cumberland and 6in light cruisers Ajax and New Zealand Achilles - correctly anticipated her destination. Unfortunately “Cumberland” was by now in the Falklands. At 06.14 on the 13th, 150 miles east of the Plate Estuary, “Graf Spee” (Capt Langsdorff) was reported to the northwest of the three cruisers [1 - see map]. Faced with “Graf Spee's" heavier armament, Cdre Harwood decided to split his force in two and try to divide her main guns. “Exeter” closed to the south [2] while the two light cruisers worked around to the north [3], all firing as they manoeuvred.

“Graf Spee” concentrated her two 11in turrets on “Exeter” which was badly hit [4]. By 06.50 all ships were heading west [5], "Exeter” with only one turret in action and on fire. “Ajax” and “Achilles” continued to harry the pocket battleship from the north [6], but at 07.25 "Ajax" lost her two after turrets to an 11in hit [7] and “Achilles” already had splinter damage. HMS Exeter was forced to break off and head south for the Falklands [8], but "Graf Spee" failed to press home her advantage. By 08.00, still with only superficial damage, she headed for the neutral Uruguayan port of Montevideo, the cruisers shadowing [9]. “GRAF SPEE” entered port at midnight. As other Allied hunting groups headed for the area, much diplomatic manoeuvring took place to hold her there. Finally, on the 17th, Capt Langsdorff edged his ship out into the estuary where she was scuttled and blown up. Only “Cumberland” had arrived by this time. Langsdorff then committed suicide.

Monthly Loss Summary: 7 British, Allied and Neutral ships of 38,000 tons in the Atlantic from all causes; 1 German pocket battleship.


4th - Returning from the hunt for the German battle-cruisers after the sinking of "Rawalpindi" on the 23rd November, battleship "Nelson" was damaged by a mine laid by "U-31" off Loch Ewe, northwest Scotland.

4th - On patrol off the Heligoland Bight, submarine "Salmon" (Lt Cdr Bickford) sank outward bound "U-36". She was successful again nine days later. 13th - "Salmon" torpedoed and damaged German cruisers "Leipzig" and "Nurnberg" in the North Sea as they covered a destroyer mine laying operation off the Tyne Estuary, north east England.

12th - Battleship Barham was involved in two incidents. On the 12th in the North Channel separating Northern Ireland and Scotland, she collided with and sank one of the screening destroyers DUCHESS. 28th - Two weeks later, "Barham" was torpedoed and damaged off the Hebrides by "U-30" (Lt Cdr Lemp)

Merchant Shipping War - Trawlers were the main victims of the first successful attacks by German aircraft off the East Coast. By the end of March they had accounted for 30 vessels of 37,000 tons. Losses from mines remained high - 33 ships of 83,000 tons in December.

Monthly Loss Summary: 66 British, Allied and Neutral ships of 152,000 tons in UK waters.





30th - Attacking Thames-out convoy 0A80 to the west of the English Channel, “U-55” was destroyed in a joint action by an RAF Sunderland of No 228 Squadron, sloop “Fowey“ and destroyer “Whitshed”. This was the first successful air/sea attack, not to be repeated for another five months.

Monthly Loss Summary: - 9 British, Allied and neutral ships of 36,000 tons in the Atlantic from all causes; 1 German U-boat.


Western Europe - German plans for a Western offensive (Operation 'Gelb') were postponed. Planning went ahead for the invasion of Norway under codename 'Weserubung'.

1st - AA cruiser Coventry was damaged in an air raid on the Shetland Islands, north of Scotland.

7th - Home Fleet submarines suffered heavy losses in the Heligoland area at the hands of minesweeper patrols, starting with SEAHORSE. On the same day UNDINE was sunk. 9th - Two days later STARFISH was also lost. British submarine operations in the Heligoland Bight were abandoned.

19th - As destroyer GRENVILLE returned from contraband control off the Dutch coast she was lost on a destroyer-laid mine off the Thames Estuary.

21st - Searching for a reported U-boat off the Moray Firth, destroyer EXMOUTH was torpedoed by “U-22” and lost with all hands.

Merchant Shipping War - U-boats were particularly active in the Moray Firth area off the Scottish coast and in the rest of the North Sea through until March 1940. In January alone they sank 14 ships - all neutrals.

Monthly Loss Summary: 64 British, Allied and neutral ships of 179,000 tons in UK waters.




5th - “U-41” sank one ship from Liverpool-out convoy OB84 south of Ireland, but was then sent to the bottom by the lone escort, destroyer “Antelope”. 23rd - Destroyer “Gurkha” on passage south of the Faeroe Islands encountered and sank “U-53” returning from patrol in the Western Approaches.

Monthly Loss Summary: 17 British, Allied and neutral ships of 75,000 tons from all causes; 2 German U-boats.


12th - “U-33” on a minelaying operation in the Firth of Clyde, western Scotland was sunk by minesweeper “Gleaner”.

16th, The “Altmark” Incident - "Altmark" was “Graf Spee's” supply ship with Merchant Navy prisoners onboard. She was located off Norway and took refuge in Jossingfiord, within territorial waters. That evening destroyer “Cossack” (Capt Vian) went alongside with a boarding party and after a short struggle released the prisoners with the cry 'The Navy's here!'

18th - In an attack on Norway/UK convoy HN12, destroyer DARING was sunk by “U-23” in the northern North Sea, east of the Pentland Firth. 25th - A week later, Norway/UK convoy HN14 was attacked. German “U-63” was sighted by escorting submarine “Narwhal” and sent to the bottom by destroyers “Escort”, “lmogen” and “lnglefield”.

22nd - German destroyers were attacked in error by their own aircraft in the North Sea and ran into a minefield laid by Royal Navy destroyers. “LEBERECHT MAASS” and “MAX SCHULTZ” were lost northwest of the German Frisian Islands. “U-54” was presumed lost in the same field.

Russo-Finnish War - Britain and France planned to send aid to Finland, and thus allow them to occupy Narvik in northern Norway to cut back Swedish iron ore supplies to Germany.

Monthly Loss Summary: 46 British, Allied and neutral ships of 152,000 tons in UK waters; 3 German U-boats


MARCH 1940


Canada - William MacKenzie King, Prime Minister of Canada was re-elected by a massive majority in support of the government's war policies.

German Raiders - Converted from a merchantman and heavily armed, auxiliary cruiser “Atlantis” sailed for the Indian Ocean round the Cape of Good Hope. In 1941 she moved into the South Atlantic, and operations lasted for a total of 20 months until her loss in November 1941. She was the first of nine active raiders, seven of which went out in 1940. Only one ever broke out for a second cruise. Their success was not so much due to their sinkings and captures - a creditable average of 15 ships of 90,000 tons for each raider, but the disruption they caused in every ocean. At a time when the Royal Navy was short of ships, convoys had to be organised and patrols instituted in many areas. In 1940 raiders accounted for 54 ships of 370,000 tons. The first German raider was not caught until May 1941 - 14 months on.

20th - Home Fleet battlecruisers to the north of the Shetlands covered a cruiser sweep into the Skagerrak. German U-boat “U-44” was sighted and sunk by escorting destroyer “Fortune”.

Battle of the Atlantic - U-boats started withdrawing from the Western Approaches to prepare for the German invasion of Norway. In preparation for the vital transport role she, sister "Queen Mary" and other fast liners played in the Allies strategic moves, the nearly completed "Queen Elizabeth" sailed independently on her maiden voyage from Scotland to New York for conversion to a troopship.

Monthly Loss Summary: 2 British, Allied and neutral ships of 11,000 tons from all causes; 1 U-boat.


Russo-Finnish War, Conclusion - A peace treaty on the 13th brought the war to a close, with Finland ceding the disputed territory to the Soviet Union.

11th - “U-31” was bombed and sunk by a RAF Blenheim of Bomber Command in the Heligoland Bight. She was salvaged and recommissioned, but finally lost eight months later.

16th - Home Fleet was bombed in Scapa Flow and heavy cruiser Norfolk damaged.

Norway - Later in the month, and in spite of abandoning plans to help Finland, Britain and France decided to disrupt Swedish iron ore traffic to Germany by mining Norwegian waters (Operation 'Wilfred'). Plans were also made to land troops - from south to north, at Stavanger, Bergen, Trondheim and Narvik to forestall any German retaliation (Operation 'R4). The entire operation was timed for 8th April.

Merchant Shipping War - Since September 1939, 430,000 tons of shipping had been sent to the bottom by mines around the coasts of Britain - a loss rate only second to U-boats. Now the Royal Navy slowly countered magnetic mines with the introduction of ship-degaussing and 'LL' minesweeping gear. Although mines - contact, magnetic and later acoustic remained a threat throughout the war, they never again represented the danger of the first few months.

Monthly Loss Summary: 43 British, Allied and neutral ships of 96,000 tons in UK waters; 1 German U-boat



In the period September 1939 to the end of March 1940, much of the Royal Navy's efforts had been directed to organising the protection of trade both to and from Britain as well as around the British Isles. The small number of U-boats operating out in the Atlantic in the South Western Approaches as well as in the North Sea had their successes, but mainly against independently-routed shipping. Losses in UK waters were high from both U-boats and mines, but from now on enemy submarines disappeared from UK coastal areas for more than four years until mid-1944. The struggle to keep Britain in the war moved further and further out into the Atlantic and even further afield over the years to come.

Total Losses = 402 British, Allied and neutral ships of 1,303,000 tons (186,000 tons per month)

By Location


Number of British, Allied, neutral ships

Total Gross Registered Tonnage

North Atlantic


371,000 tons

South Atlantic


49,000 tons

UK waters


883,000 tons

By Cause

Causes* in order of tonnage sunk

Number of British, Allied, neutral ships

Total Gross Registered Tonnage

1. Submarines


765,000 tons

2. Mines


430,000 tons

3. Warships


63,000 tons

4. Aircraft


37,000 tons

5. Other causes


8,000 tons

* The identifying numbers for each cause e.g. "1. Submarines" is retained for all Trade War summaries, and added to as new weapon types appear e.g. "6. Raiders". The trends in losses due to the different causes can thus be followed

Western Europe was about to erupt. There was a lull in the Battle of the Atlantic as U-boats were withdrawn for the Norwegian campaign, and before surface raiders started operations and long-range aircraft and U-boats emerged from bases in France and Norway. Around the British Isles, aircraft and mines continued to account for merchant ships of all sizes, especially during the confused months of May, June and July 1940. During this time German E-boats commenced attacks in coastal waters. (Enemy or E-boat was the English term for German motor torpedo boats or S-boats, not to be confused with the heavily armed torpedo boats or small destroyers with their 'T' designation.) The comparatively low monthly average of 186,000 tons of merchant shipping lost in the first seven months was not seen for any more than a month or two for three long and deadly dangerous years - until mid 1943.


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