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September 1939 - May 1940

"Naval & Military Campaign Summaries of World War 2" - an ideal way to come to grips with the complexity of World War 2 on land and sea.

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Starting Conditions - Strategic and Maritime Situation

Areas under direct Allied control of Britain and France included Canada, Bermuda, many of the West Indies, British and French Guiana, islands in the South Atlantic, much of the Atlantic seaboard of Africa, and the fortress of Gibraltar. The one major defensive gap was the lack of bases in Eire to cover the Western Approaches to Britain. In contrast Germany was restricted to short North Sea and Baltic coastlines, and its exits to the Atlantic passed through the North Sea and the Allied controlled English Channel, which American ships and troops would come to know so well four and a half years later. However Britain's survival, and ultimately Allied success in Europe, depended on the Atlantic trade routes. Germany's did not.

The primary maritime tasks of the Allies were based on the assumption that Britain and France would face the European Axis powers of Germany and Italy. The British Navy was responsible for the North Sea and most of the Atlantic, and both Allies shared in the defence of the Mediterranean. Mussolini did not go to war for another nine months.

Declaration of War - Following the German invasion of Poland on the 1st September, Britain and France demanded the withdrawal of German forces. The ultimatum was rejected, and the Allies together with Australia, New Zealand and India declared war on the 3rd. South Africa followed on the 6th and Canada on the 10th. Italy announced her neutrality.


Neutrality Announced - On the 5th, President Roosevelt declared the neutrality of the United States in accordance with the 1937 Neutrality Act. This included a ban on the sale of arms and munitions to all belligerents.

Military Strength - On the 8th, he proclaimed a "limited national emergency" and increased the strength of the armed forces. This included Naval enlisted men from 110,000 to 145,000 and Marine Corps from 18,000 to 25,000. Retired Navy and Marine officers and men could also be recalled to active duty as needed.

Neutrality Patrol - The President also ordered the organisation of a Neutrality Patrol to protect the neutrality of the Americas and report any movement of belligerent forces towards the coasts of the United States or the West Indies. The Neutrality Patrol was formed on the 12th under the command of Commander Atlantic Squadron (Rear-Adm A W Johnson). Organised into eight groups consisting mainly of cruisers and destroyers, some with patrol aircraft support, it covered the coast from Canada down to the Caribbean. Battleships and a carrier were held in reserve.


Battle of the Atlantic - The six year long Battle started the day war was declared by Britain, when the British liner "Athenia" was sunk as a suspected armed merchant cruiser by a German U-boat northwest of Ireland. Survivors were rescued by a number of ships including the American "City of Flint" which was again in the news in October, but the 112 dead included a number of US citizens. Hitler initially ordered a tightening of controls on U-boat warfare, but this did not prevent the British Admiralty immediately putting convoy plans into operation. By the end of September 1939 convoys were sailing (1) from Britain out into the Atlantic, (2) to Britain from Gibraltar and West Africa, and (3) from Halifax, Nova Scotia in the HX convoys. One of these latter convoys saw the loss of USS "Reuben James" with HX156 two years later. Although only limited protection was possible, convoys suffered little harm over the next nine months and most losses due to U-boats were among independently routed and neutral merchantmen.

The first U-boat lost was "U-39", sunk by British destroyers north of the British Isles on the 14th, but three days later to the south west of Ireland, British fleet carrier "Courageous" on anti-U-boat patrol was torpedoed and went to the bottom with heavy loss of life. Far to the south, off Brazil on the last day of the month, German pocket battleship "Admiral Graf Spee" sank her first Allied merchantman.

Losses For September in the Atlantic:
20 Allied and neutral merchant ships of 110,000 tons and 1 British fleet carrier
2 German U-boats sunk by British destroyers off the British Isles.


Western Front - The first units of the eventually half a million strong British Expeditionary Force crossed the English Channel to join the French Army.

Air War - RAF aircraft made their first attacks on German warships in their bases.

German Code Breaking - An important step was taken towards the eventual successful conclusion of the war when the British Code and Cipher School in England moved to Bletchley Park. From here, through the "Ultra" programme, the German "Enigma" codes were eventually broken. Working on earlier Polish and French successes, this led to the Allies penetrating to the very heart of Axis planning and operations.  "Ultra" also contributed significantly to the defeat of the U-boat, probably the greatest threat faced by the Western Allies throughout the war. Early signs of the U-boat danger were not only evident in the North Atlantic, but in the attacks with torpedo and magnetic mine that immediately started around British coasts.

Poland - The German advance into Poland continued and on the 17th September, Russia invaded from the east. Warsaw surrendered to the German Army on the 28th, and next day the country was partitioned in accordance with the Soviet-German Pact. The last of the Polish Army surrendered on the 5th October and Poland entered its long dark years of brutal oppression.



Atomic Bomb - In an act that would eventually bring about the end of World War 2, President Roosevelt on the advice of Albert Einstein established an Advisory Committee on Uranium that led to the development of the atomic bomb. Six months later, just as the "phoney war" ended and Europe exploded, the British government sets up its own organisation to oversee nuclear research.

Neutrality Zone - On the 2nd October by the Act of Panama, a Pan-American Conference of Foreign Ministers established a 300-mile wide neutrality zone off the coasts of the Americas, but excluding Canada. This was policed at least as far south as Trinidad by the eight US Navy groups of the Neutrality Patrol. All hostile action or military operations by the belligerent powers were forbidden in this area.


German Warships - As German pocket battleship "Graf Spee" claimed more victims in the South Atlantic, the British and French Navies formed hunting groups in the Atlantic and Indian Oceans. By now the Allies were blockading Germany, and Germany had announced its own counter-blockade, both steps leading to incidents with a protesting United States. In the North Atlantic, the second pocket battleship "Deutchland" captured the US freighter "City of Flint" as a contraband carrier while on passage from New York to Britain. After accounting for two more ships, "Deutschland" was ordered home, reaching Germany in November to be renamed "Lutzow".

Losses For October in the Atlantic:
22 Allied and neutral merchant ships of 133,000 tons
2 German U-boats by British destroyers off Ireland.


Western Front -  Hitler ordered planning to begin for the invasion of France and the Low Countries.

War at Sea - The German Air Force launched its first attacks on British warships and merchantmen. The Royal Navy suffered a tragic loss when anchored battleship "Royal Oak" was sunk by "U-47" in the major base of Scapa Flow, north of Scotland. Three U-boats were lost on Allied mines in the Straits of Dover.



Neutrality Act - The Neutrality Act was amended on the 4th November to allow the supply of arms to belligerents on a "cash and carry" basis. In practical terms, this meant supplying the British and French only. American shipping and citizens were banned from entering defined war zones, including the seas around the British Isles.

U.S. Navy -  "Benson/Gleaves" class destroyer "Benson" (1,800t, 5-5in, 10tt) was launched by Bethlehem, Quincy. A total of 96 of these pre-war-designed destroyers were in the water by early 1943. The numerous ships of the "Fletcher" class, first launched in 1942, the "Allen M Sumner's" from 1943, and the "Gearing's" from 1945 followed them. 


German Warships - For most of the war, the few powerful German capital ships exercised a great influence on British Navy operations in the Atlantic, and to a lesser extent those of the U.S. Navy. As a foretaste, battlecruisers "Gneisenau" and "Scharnhorst" on a short sortie into the waters near Iceland sank a British armed merchant cruiser.

Losses For November in the Atlantic:
6 Allied and neutral merchant ships of 18,000 tons
1 German U-boat by British destroyers north of Scotland. 


Mine Warfare - Magnetic mines laid by U-boats, surface ships and aircraft continued to be a serious threat around British coasts, and in November 1939 accounted for 27 merchant ships of 121,000 tons, two British destroyers sunk and a cruiser seriously damaged. However, such countermeasures as ship-degaussing and the LL sweep became possible when a mine was recovered in the Thames Estuary leading up to London.  

Russo-Finnish War - Europe moved steadily towards all-out war. Negotiations between Russia and Finland on border changes and the control of islands in the Gulf of Finland broke down. On the 30th November, Russia invaded. The Finns resisted fiercely and the war dragged on into March 1940



Allied Blockade - As the German liner "Columbus" of 32,000 tons broke out into the Atlantic from the Gulf of Mexico, she was intercepted by a British destroyer to the east of Cape May, New Jersey on the 19th and scuttled. The British blockade of Germany continued to cause difficulties and the US protested about the seizure of mail bound for Europe.

U.S. Navy - Light cruisers "St Louis" (CL49) and "Helena" (CL50) - both 9,800t, 15-6in guns - the last of nine "Brooklyn" class ships were commissioned at Newport News and New York respectively. 


War at Sea - On the 13th December, east of Uruguay in the South Atlantic, a British heavy and two light cruisers encountered and damaged the 11 inch gunned "Graf Spee" in the running "Battle of the River Plate". Putting into Montevideo for repairs, the pocket battleship was scuttled on the 17th on Hitler's orders. The heavy cruiser that took part was HMS Exeter, destined to share the fate of the USS Houston half a world away in early 1942.


Losses For December in the Atlantic:
7 Allied and neutral merchant ships of 38,000 tons
1 German pocket battleship and 1 outward bound U-boat by British submarine in the North Sea



U.S. Navy - Two of the most senior appointments in the US Navy were made at this time - one civilian, the other naval. Assistant Secretary Charles Edison who had been Acting Secretary since the death of Claude Swanson in July 1939 was confirmed as Secretary of the Navy. Adm James O Richardson relieved Adm Claude C Bloch as Commander-in-Chief, United States Fleet.

United States/Japanese Affairs and the Pacific - Even before the European war began, Japan had manoeuvred to complete the conquest of China. By the end of 1938, north east China as far south as Shanghai together with all the major ports were in their hands, and in February 1939, the large island of Hainan in the South China Sea was occupied. These and subsequent events continued to sour US/Japanese relations, and led inexorably towards total world war. For example, on the 26th January 1940, the US-Japanese Trade Treaty of 1911 was allowed to expire because of Japan's position in China.


U-boat War - In the hard fought battle against the U-boat, comparatively few of the 780 German submarines lost were destroyed in the first two years of the war, and of these, most fall victim to the surface ships of the British Navy. However the first indication of the eventual part played by aircraft was when an RAF Sunderland flying boat shared in the sinking of "U-55" at the end of the month off the southwest coast of Britain. Allied aircraft went on to sink around 290 U-boats.

Losses For January in the Atlantic:
9 Allied and neutral merchant ships of 36,000 tons in the North and South Atlantic
1 German U-boat by British escorts and RAF aircraft off southwest Britain.


Western Front & Norway - German plans for a Western Offensive into Europe involving attacks on Holland, Belgium, Luxembourg and France were postponed. Instead, planning went ahead for the invasion of Denmark and Norway.



Losses For February in the Atlantic:
17 Allied and neutral merchant ships of 75,000 tons
2 German U-boats by British destroyers off the Faeroes and Ireland. 


Russo-Finnish War - Britain and France decided to send aid to Finland. This would allow them to occupy Narvik in northern Norway, and partly cut off Swedish iron ore supplies to Germany.

War at Sea - British warships off Scotland sank two more German U-boats.

MARCH 1940


U.S. Navy -  Eleven "Atlanta" class light cruisers were completed through to 1946, half by the end of 1942. The name ship "Atlanta" (6,700t, 16-5in) was laid down in March 1940 and launched in September 1941.

United States/Japanese Affairs and the Pacific - Japan established a Chinese puppet-government in Nanking.


German Raiders - The German Navy added heavily armed merchant ship to its armoury of U-boats and surface warships ranged against Allied and especially British shipping. The first German raider or auxiliary cruiser to leave was "Atlantis", one of nine that eventually broke out to create havoc not only in the Atlantic but also across the Indian and Pacific Oceans. Their success was not so much due to their sinkings and captures - an average of 15 ships of 90,000 tons for each raider - but to the widespread disruption they caused. Convoys had to be organised and patrols instituted in many parts of the world. In 1942, by which time they had nearly been swept from the oceans, the US liberty ship "Stephen Hopkins" in one of the few single ship actions of the war, put paid to the "Stier".

Troopships - In another aspect of the war at sea, the newly completed giant liner "Queen Elizabeth" sailed from Britain for New York, later to be converted into a troopship. Used for transporting British and Dominion troops at first, she, sister "Queen Mary" and other fast liners came to play a major part in the build-up of American forces for the eventual invasion of Europe.

Battle of the Atlantic - German U-boats started withdrawing from the Atlantic in preparation for the invasion of Norway.

Losses For March in the Atlantic:
2 Allied and neutral merchant ships of 11,000 tons
1 German U-boat by British destroyer off the Shetlands. 


Russo-Finnish War - A peace treaty on the 13th March ended the war, with the transfer of Finnish territory to the victor.

Norway - Later in the month, and having abandoned plans to help Finland, Britain and France decided to disrupt Swedish iron ore traffic by mining Norwegian waters. Troops would also be landed if necessary to forestall German retaliation.

Mine Warfare - Magnetic mines continued to take a heavy toll of Allied and neutral shipping in British waters, but were now countered by ship degaussing and the use of LL minesweeping gear. The first acoustic mines were also used in British waters from August 1940, and their main counter was the towed hammer box. Mines remained a threat throughout the war, but were never again the danger they represented in the first few months.

APRIL 1940


U.S. Navy - Large carrier "Wasp" (14,700t, 76 aircraft) was commissioned at Bethlehem, Quincy, the only one of her class. The next class to enter service was the numerous and successful "Essex" carriers.

United States/Japanese Affairs and the Pacific - The United States Fleet commanded by the C-in-C, Adm James Richardson left the West Coast for exercises in Hawaiian waters. 


Losses For April in the Atlantic:
4 Allied and neutral merchant ships of 25,000 tons
1 German U-boat by British destroyer off the Shetlands. 


Invasion of Denmark and Norway - German forces including most of the Navy took part in the 9th April invasion of Denmark and Norway. Copenhagen was soon occupied and Denmark surrendered on the day of invasion. German troops landed at a number of points in Norway. Soon in control of the south and centre, they were pushing north by the end of the month to relieve the forces landed at Narvik in the north

The British Home Fleet sailed too late to intercept, but the German landings led to heavy German naval losses. Heavy cruiser "Blücher" was sunk by Norwegian shore defences near Oslo, cruiser "Karlsrühe" by a British submarine, and in the first such successful attack of the war, sister ship "Königsberg" by British Navy dive-bombers at Bergen. All ten German destroyers taking part in the occupation of Narvik were also lost in the two Battles of Narvik. In the first battle, on the 10th, five British destroyers went in to attack supply ships and sank two of the Germans for the loss of two of their own. Three days later a battleship and more destroyers entered the fiords and sank a U-boat and the remaining eight destroyers.

In the middle of the month, British and French troops landed in central Norway to hold the Germans around Trondheim, and also in the north to prepare for a ground attack on Narvik itself. But the Germans were well established with control of the air, and by month's end the Allied forces in central Norway were being evacuated. 

Allied Evacuations - Norway marked the start of nearly two years of Allied evacuations from north and south Europe and later Asia, during which the British Navy in particular suffered heavy losses, usually to air attack. Norway was no exception. During the campaign one cruiser was sunk, three damaged, and four destroyers including one French and one Polish were lost, all to German aircraft. The days of carrier-based air cover and powerful AA defences were some years in the future, but fortunately for the Allies, the U-boats at this time suffered major torpedo defect and their many attacks caused few losses.

MAY 1940


Military Strength - With the German invasion of Western Europe, Pres. Roosevelt asked Congress for funds totalling $1 billion to significantly increase US military strength, and equip the Navy and Army with 50,000 aircraft each year.  He also announced plans to re-commission more destroyers.

United States/Japanese Relations and the Far East - Japan proclaimed a "Greater East Asia Co-Prosperity Sphere" over much of Asia.  The President ordered the US Fleet to remain in the Pacific, based at Pearl Harbor as a deterrent force for the foreseeable future. 


Iceland, Dutch West Indies, Greenland - As events unfolded in Western Europe, the Allies took steps to protect their strategic position. British troops landed in Iceland to start setting up the air and sea bases that become vital to the defence of the sea lanes between North America and Britain. Soon after the German invasion of Holland, the Allies went ashore on the Dutch West Indies islands of Aruba and Curacoa to protect the oil installations. Greenland also asked the United States for protection.

Losses For April in the Atlantic:
10 Allied and neutral merchant ships of 55,000 tons 


Norwegian Campaign - British, French and Polish forces prepared to attack Narvik as the Germans continued to push north themselves.   As they did, a British troop-carrying cruiser ran aground near Bodo becoming a total loss, and only now were the first modern RAF fighters flown ashore from Royal Navy carriers. Narvik was captured on the 28th but only to allow the installations to be destroyed. With the invasion of France, the decision had already been taken to abandon Norway.

United Kingdom - The Allies failures in Norway led to one of the most important political developments of the war. British Prime Minister Neville Chamberlain resigned and Winston Churchill took his place on the 10th May.

Invasion of Holland, Belgium and France - Germany invaded Holland, Belgium and Luxembourg on the day Churchill came to power. Anglo-French troops moved into Belgium but the main German thrust was further south in the centre through the Ardennes. By the 13th May they had crossed into France at Sedan, and the German Panzers were breaking through towards the Channel coast to trap the Allied armies in Belgium and northern France. Rotterdam was blitzed on the 14th and the Dutch army surrendered the next day. As the Allies retreated from Belgium, German forces entered Brussels on the 17th.

As in Norway, the Germans usually had air superiority and the British and French Navies suffered heavily, especially in destroyers. Even before the Dunkirk evacuation started, three British and four French destroyers were lost off the coasts of France and the Low Countries.  

On the 20th, German armour reachesd the Channel near Abbeville and pushed north as the British and French fall back on Dunkirk.  

The British decide to evacuate their Expeditionary Force from Dunkirk, and hoped to lift off 45,000 men in two days starting from the 26th. Under heavy attack by air, sea and from the shore, Operation "Dynamo" was endangered by the collapse of the Belgium Army and its surrender on the 28th, but continued into early June. Three more British and two French destroyers went down off the evacuation beaches before May was out.  

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