World war II timeline - May 1940

1 May 1940	British ships begin transporting soldiers off Namsos, Norway. French counterintelligence in Berne, Switzerland, confirms May 8-10 as the German date of attack, with an attack on the whole front, focusing on Sedan. Czech agent and German military intelligence service member Paul Thümmel reports to French intelligence via The Hague that a German offensive against the West would begin May 10. Germans change key settings on Enigma ciphering machines.
3 May 1940	The Allied Expeditionary Force in Norway completes its withdrawal from Namsos and Andalsnes. The French destroyer Bison is bombed and sunk in the North Sea, while escorting a troop convoy. The British destroyer Afridi is bombed and sunk in the North Sea, while escorting a troop convoy from Norway to England.
5 May 1940	The Norwegian mountain fortress Hegra surrenders. German armed merchant raider Widder leaves Germany.
7 May 1940	French General Maurice-Gustave Gamelin restores leave for Army soldiers. Adolf Hitler sets May 10 as the date for Operation Sichelschnitt (sickle cut).
9 May 1940	In England, Labour Party leaders Arthur Greenwood and Clement Attlee refuse to form a unified government with the Conservatives so long as Neville Chamberlain is Prime Minister. German General Hans Oster warns the Dutch military attaché in Berlin for the third time in a week that a German offensive against the West is imminent.
10 May 1940	Foreign bombers over Basel, Switzerland, drop a few bombs on the city, as Swiss anti-aircraft guns fire on them. Adolf Hitler arrives at his bunker near Aachen, Germany, to direct operation Fall Gelb (Case Yellow), the attack on western Europe. German forces begin operation Sichelschnitt (Sickle Stroke), a surprise assault against Holland, Luxembourg, Belgium. Fleets of Luftwaffe bombers and fighters take off to attack western Europe. German parachute and airborne forces begin landing to secure key bridges in Holland at Rotterdam, Dordrecht, and Moerdijk, and in Belgium at Maastricht. Some parachutists are disguised as Netherland soldiers, farm boys, and Roman Catholic nuns. German planes begin bombing Antwerp, Belgium. Four German bombers drop bombs on Méry-sur-Oise, twenty miles from Paris, France. German Chancellor Adolf Hitler gives his Order of the Day to the German troops, saying "The fight beginning today decides the fate of the German nation for the next 1000 years.". 76 German divisions cross a 175-mile front into Holland, Belgium, and Luxembourg. German Foreign Minister Joachim von Ribbentrop informs the foreign press that Germany had seized the initiative by anticipating Anglo-French aggression in the Ruhr area over Netherlands and Belgian territory. He presents evidence that Netherlands and Belgium were not acting as neutrals, that they were defending only on the German border, and allowing British and French assistance in attempting revolution in Germany. German forces in the Netherlands, Belgium, and Luxembourg would ast as protectors and take steps to ensure their neutrality. Twenty-one 10-man DFS230 gliders descend over Dutch territory, having been pulled by Junker 52 transport planes from airfields near Cologne, Germany. Ten gliders land near key bridges, nine others landing on the roof of Belgium's Fort Eban Emael. Engineers quickly set explosive charges in gun barrels, casemates, and exit passages, sealing in the 650-man garrison. (After just over a day, with the arrival of German ground forces, the fort is taken.) The government of the Netherlands declares a state of war with Germany. British and French troops enter Luxembourg, Belgium, and the Netherlands to counter the German attack. The German ambassador to Belgium notifies the Belgian Foreign Minister of the invasion of the country. The response is protest, and announcement of resistance. The Belgian government calls on English and French troops to enter the country to aid in its defence. The Belgian Government declares Brussels an open city, with no troops defending it, and for no troops to pass through the city. British soldiers cross the North Sea, landing on the Netherlands coast at several points. The Netherland East and West Indies and Dutch Guiana formally declare the existence of a state of war with Germany. The Governor places the islands under martial law, and warns that any help from other nations would be rejected as unwelcome. 32 British Battles bombers attack German columns in Luxembourg. 13 planes are shot down; all others are damaged. British forces occupy Iceland. Switzerland orders general mobilization for defence for the following day, and declares a "precautionary state of war" as of midnight. Quote by French General Maurice-Gustave Gamelin: "Germany has engaged against us in a struggle to the death.". Britain's Prime Minister Neville Chamberlain resigns. At Buckingham Palace, London, England, King George VI asks Winston Churchill to form a new government. German forces complete overrunning Luxembourg, and taking Maastrich in the Netherlands, and Malmedy in Belgium. First major German air attacks on French objectives take place: air fields, railroads and stations, coal mines, and factories. Germans airdrop reinforcements into Rotterdam, Netherlands. British Prime Minister Winston Churchill completes the forming of his government. Clement Attlee is made Lord Privy Seal, Arthur Greenwood is made Minister Without-Portfolio. Anthony Eden is made Secretary of State for War. Sir Archibald Sinclair is made Air Secretary.
11 May 1940	German parachute troops begin landing in the Dordrecht area of the Netherlands. German parachute troops land behind the French Maginot Line. King Leopold places himself at the head of the Belgian army. British fleet air arm makes two bombing runs on Bergen, Norway, striking a German training ship and ground fuel tanks. The British Admiralty reports it has created a vast new minefield in Norwegian waters, extending from Bergen to Namsos, 20-70 miles offshore. German bombs hit a British battleship and a cruiser off Narvik, Norway. British and French troops land in the Netherlands West Indies Islands of Curacao and Aruba, to aid the Netherlands local authorities in the security of the islands. Yugoslavia signs a trade agreement with Soviet Russia. French mechanized troops cross the Belgian frontier into the Netherlands. Netherlands forces recapture Dordrecht. British Prime Minister Winston Churchill gives Bomber Command authority to attack Germany. Eight British Battles bombers attack German columns entering Luxembourg. Seven planes are shot down, the eighth crashes on return in England. The Romanian Government of Premier George Tatarescu replaces several pro-German Ministers with pro-France officials. Tatarescu declares the nation will continue its policy of neutrality, with friendship for Britain and France. The Japanese Foreign Minister notifies diplomatic representatives of the Netherlands, Germany, Britain, France, USA, and Italy that it would not tolerate any change of nationality control of the Netherlands Indies. Any outside interference would be considered an extension of the war to the Orient, which Japan would forcibly oppose Netherlands troops recapture the village Mill, southeast of Nijmegen. Hermann Göring demands that the Swedes allow passage of trains to Norway, filled with German artillery and other war supplies. Swedish negotiators refuse to allow it. Belgian Fort Eben Emael surrenders to German infantry. About 1000 prisoners are taken. Netherlands troops withdraw from the frontier, after four hours fighting, due to German planes landing thousands of parachute troops behind Dutch lines toward The Hague and Rotterdam. German artillery begins intense firing near the Saar River, west of Vosges, France.
12 May 1940	British Royal Air Force planes bomb Essen and two other German towns. German troops begin initial skirmishes with French troops in the Warndt sector, continuing throughout the day. Nine British Blenheim bombers attack a German column on the Maastricht - Tongres road. Seven planes are shot down. Five British Battles bombers attack bridges over the Albert Canal. They break one bridge, but four planes are shot down. Twenty-four British Blenheim bombers attack bridges and roads in Maastricht. Ten bombers are shot down. The Dutch Crown Princess and family embark on British destroyer Codrington from Ijmuiden. British cruisers Galatea and Arethusa take the Dutch gold reserve to England. German forces break through the Maastricht-Hasselt defence line in Belgium. Germans begin crossing the River Meuse on two undemolished bridges in the Maastricht region. A British Royal Navy battleship accidentally strikes anti-submarine trawler Ypres, sinking it. All eighteen crew members survive. In the Netherlands, German forces capture Harlingen on the North Sea, and occupy the northern provinces. Sweden begins nation-wide city blackouts. Italian Premier Benito Mussolini instructs the Chief of Army Staff and Under-Secretary of War to further perfect the western Alpine frontier defences. Spain's Foreign Ministry issues a communiqué reaffirming its policy of neutrality. Netherland troops recapture Waalhaven Airport and regain control of most of Rotterdam, forcing Germans to retreat south of the Maas River.  German 1st and 10th Panzer groups reach the east bank of the Meuse River at Sedan.
13 May 1940	Amsterdam, Netherlands, is hit by over fifty aerial bombs. Adolf Hitler awards the Knight's Cross of the Order of the Iron Cross to Captain Koch and seven others for the successful attack of the Eben Emael Fort near Liége, Belgium, and bridges over the Albert Canal. The German Luftwaffe concentrates an attack on the city center of Rotterdam, Netherlands, without regard for civilian casualties. About 1000 civilians are killed. German 9th Panzer Division breaks through the frontier with Netherlands, and rushes to bridges in the Dordrecht - Moerdijk - Rotterdam area, cutting the Netherlands in two. German units passing through Luxembourg advance into Belgium through the Ardennes forest, crossing River Ourthe, heading to River Semoy. German forces bypass Liége forts in Belgium, capturing Liége itself. A German mechanized column clashes with Allied armored forces near St. Trond, 22 miles northwest of Liége. The Holland America freighter Blommersdyk arrives at Hoboken, New York, USA, with a large shipment of gold for safe-keeping at the New York Federal Reserve bank. German 7th Panzer Division lead by General Erwin Rommel crosses the Meuse River at Dinant. At Bjerkvik, Norway, seven miles north of Narvik, three battalions of French alpine troops and a Norwegian battalion land, capturing the town, and prepare for an assault on Narvik. The governments of Great Britain, Netherlands, and France assure Japan that no change of control of the Netherlands Indies is intended. The German government warns Great Britain, Belgium, France, and the Netherlands that for any German parachute soldier shot contrary to international law, ten surrendered French soldiers would be shot. French artillery and Allied air bombs destroy part of the Istein railroad tunnel, five miles north of the Swiss border, cutting off a section of vital army rail transportation to part of the German Westwall fortifications. Netherlands forces regain control of Rotterdam north of the Maas River, and Noorder Island. German 1st Rifle Regiment of 19th Armored Corps crosses the Meuse River at Sedan, under cover of continuous light Luftwaffe attacks on defenders. Engineers complete a bridge across the river by daybreak. Queen Wilhelmina of the Netherlands escapes to London, England, on British destroyer Hereword. British Prime Minister Winston Churchill makes a speech in the House of Commons, including "... I have nothing to offer but blood, toil, tears and sweat. If you ask me, what our war aim is, I give you only one answer: Victory! Victory whatever the cost!". The Netherlands government and others embark British destroyer Windsor for England. Munich, Germany, radio station reports Adolf Hitler saying Germany possesses a "death-dealing" wave or ray, obtained from splitting atoms, which can exterminate any living creature within a 1000-foot radius, for which no known protection has yet been discovered. Grand Duchess Charlotte, ruler of Luxembourg, arrives in Paris.   British Prime Minister Winston Churchill makes Bill Stephenson his prime connection with American President Franklin Roosevelt, naming him Intrepid, and sending him to Washington.
14 May 1940	Fifteen French light tanks and infantry attack the German 1st Rifle Regiment bridgehead over the Meuse River around Bulson, France, about five miles south of Sedan. (By 09:40 hours, with four tanks left, the French retreat south. German aircraft bomb Rotterdam, Holland. The British War Cabinet reacts by removing an order restraining aerial bombers from attacks near civilian areas. German forces capture Sedan and Donchery. Hong Kong authorities issue a reminder to women and children to register for evacuation in case of emergency. British Secretary of State for War Anthony Eden broadcasts a call for Local Defence Volunteers. (Within 24 hours, 250,000 men enroll in whan becomes the Home Guard.) Danish steamer Olympia unloads US$1 million of gold in Boston, Massachusettes. In Great Britain, Lord Beaverbrook is appointed minister of aircraft production. 63 British Battles bombers and eight Blenheim bombers make a series of raids on German bridgeheads over the Meuse River. 40 planes are shot down. Adolf Hitler issues Directive No. 11. Forces north of Liège to Namur are to hold down the greatest number of enemy forces. The Dutch Army is stronger than expected, and is to be broken quickly. Motorized divisions are to be transferred to Army Group A as soon as possible. German tanks strike around Gembloux between Wavre on the Dyle River and Namur on the Meuse River. (Initially about 150 French tanks hold the Germans back, but withdraw, outnumbered, the following day.) Netherlands Commander in Chief General Henri Gerard Winkelman orders the cessation of hostilities around Rotterdam and Utrecht. About 25,000 men of the army of 100,000 were killed in the fighting. Fighting in Zeeland is to continue.   Six British bombers drop four bombs half a mile inside Swedish territory, during a battle at Bjoernfjell, Norway. No damage is done.
15 May 1940	French Premier Paul Reynaud phones British Prime Minister Winston Churchill, telling him, "We have been defeated; we have lost the battle". Brithis Prime Minister Winston Churchill tells US President Franklin Roosevelt "I think myself the battle on land has only just begun. In Rijsoord, a suburb village of Rotterdam, Netherlands, Commander in Chief of Netherlands land and sea forces General Henri Winkelman signs formal capitulation of Netherlands armed forces to Germany. The German Army begins a large attack across a 60-mile front of the River Meuse from Namur to Sedan. The British War Cabinet gives Bomber Command permission to bomb the Ruhr area of Germany, east of the Rhine river. German forces attack an Irish regiment holding a railroad station on the eastern edge of Louvain, successfully taking the position. French Premier Paul Reynaud calls Winston Churchill asking for all the troops and planes he can send. Churchill decides to go himself to assess the situation. French General Maurice-Gustave Gamelin orders a retreat of Allied forces in Belgium to the River Escaut, abandoning all central and eastern Belgium, including Antwerp and Brussels. The German Army succeeds in crossing the Meuse in three places between Namur and Sedan. British bombing of German ground targets begins. 96 Wellington, Whitley, and Hampden bombers attack industrial targets east of the Rhine river. Only one plane is lost. German army general headquarters issues a statement indicating that aerial reconnaissance has shown Brussels to be allowing troops to pass through, in contravention of a declaration of being an open city. The Allies are warned to cease this action, or Brussels would be subject to military action.   American President Franklin Roosevelt shifts the US Pacific Fleet from California to Pearl Harbor, Hawaii. A concentration camp for Poles is built in Auschwitz.
16 May 1940	Greece rushes troop reinforcements to the frontier with Italian-occupied Albania. British forces launch three counterattacks on a railroad station on the eastern edge of Louvain, successfully retaking the position. Allies forces attempt a landing near Narvik, Norway, but are repulsed by German defenders. United States President Franklin Roosevelt asks Congress to approve a program of US$1.2 billion in defense spending, including 50,000 warplanes. The program is approved. German troops enter The Hague and Amsterdam, Netherlands. The United States State Department announces a warning to Americans in the British Isles to move to Ireland. French Premier Paul Reynaud tells the Chamber of Deputies: "Chancellor Hitler must win in two months; if not he is beaten, and knows it." (France surrenders six weeks after the start of the western battle.) A Swiss fighter plane shoots down a German bomber over Swiss territory, which lands north-east of Zurich. Three crewmen surrender. British King George designates May 26 as a day of prayer for peace throughout the United Kingdom. British Prime Minister Winston Churchill provides an extra ten fighter squadrons to help France, with six operating out of Kent. By nightfall, German panzers in France reach Marle and Dercy, 55 miles from Sedan. British forces in Belgium retreat to west of Brussels. German artillery batteries shell the library of the University of Louvain in Belgium until it is set afire and burned out.
17 May 1940	The French 4th Armored Division under command of Colonel Charles de Gaulle attacks German tank forces at Montcornet, but have little impact on the German advance. Twelve British Blenheim bombers attack advancing German columns near Gembloux. Eleven planes are shot down. The Belgian Government moves the capital from Brussels to Ostend on the coast. German forces break through the French land defence lines along a 62-mile front, from Maubeuge to Carignon, near Sedan. German forces in Belgium continue westward in Belgium, advancing to Brussels, capturing the city by the evening. German troops capture Louvain and Malines after heavy fighting. The Swedish government forbids all sailors on foreign vessels to leave their ships while in Swedish ports. In the Cairo Museum in Egypt, the gold sarcophagus of Tut-ankh-Amen and other treasures are moved to a secret underground bombproof vault. German panzers reach the Serre River in France, then stop. By nightfall, German 10th Panzer Division seizes a bridgehead across the Oise River near Moy, France, 70 miles west of Sedan. General Maurice Gustave Gamelin gives the order of the day to the French armies, telling them "The fate of our country and that of our Allies and the destiny of the world depend on the battle now being fought.".  British Hampden bombers make their first attack on Hamburg, Germany, with 48 planes suffering no losses in attacking oil refineries and gasoline depots.
18 May 1940	Dutch and French forces evacuate the Netherlands islands of Walcheren and South Beveland, north and west of Zeeland. Japan presents Batavia with demands of a new treaty for raw materials. German forces at the Serre River in France start moving again, heading north, away from Paris. German 2nd Panzer Division reaches St. Quentin, France, ten miles beyond Moy. Premier Paul Reynaud shuffles the French Cabinet, assuming the title of War Minister, appointing Edouard Daladier as Foreign Minister, and Marshal Henri Philippe Petain as Vice President of the Council. The German Government reincorporates the Belgian districts of Eupen, Malmedy, and Moresnet back into the Reich. The Versailles Treaty had forced those areas to be ceded to Belgium. French Premier Paul Reynaud makes an address to the nation, including "The situation is serious but certainly not desperate". British troops in Egypt reinforce the western desert frontier with Libya. The American State Department makes public a joint declaration of 21 republics of the Americas. The statement condemns the "ruthless violation by Germany of the neutrality and sovereignty of Belgium, Holland, and Luxembourg.". The German 18th Army, lead by Georg Küchler, pierce the outer ring of fortresses of Antwerp, Belgium, in two places, quickly capturing the city. German forces take over 2000 Dutch and French prisoners of war in taking the Netherlands islands of South Beveland and Schouwen. The Netherlands commander of the Zeeland Islands offers capitulation to Germany. The Swedish Council on Foreign Relations of the Swedish Cabinet rules against the transit of arms for Germany
19 May 1940	German tanks resume their westward push toward the English Channel ports. German 1st Panzer Division forces a bridgehead over the Somme River near Péronne, France, 20 miles west of St. Quentin. French General Maurice-Gustave Gamelin orders an attack into the southern flank of German General Heinz Guderian's Panzer corps. The French 4th Armored Division attacks near Laon, but fails. German forces take Maginot Line Fort Number 505, northwest of Montmedy. German forces take French towns Le Cateau and St. Quentin. French Premier Paul Reynaud appoints General Maxime Weygand to replace General Maurice-Gustave Gamelin as Chief of General Staff and Allied commander in chief. Prime Minister Churchill makes a public radio address, including "I have invincible confidence in the French Army and its leaders".
20 May 1940	German 1st Panzer Division seizes Amiens, France. German 2nd Panzer Division forces reach Abbéville, France. A battalion of German 2nd Panzer Division passes through Noyelles, reaching the sea near Abbéville, France, splitting Allied forces and trapping much of it in a northern pocket. This battalion is the first German unit to reach the Atlantic coast, just ten days after the start of the offensive.   Allies break the Enigma code that had been changed three weeks ago.
21 May 1940	At a meeting of the Australian War Cabinet, industrialist Essington Lewis is appointed Director General of Munitions Supply, and given great freedom to achieve his goals. Sir Keith Murdoch is appointed Director General of Information, with wide-ranging powers and responsibilities. Cabinet approves construction of a dry dock in Sydney capable of taking battleships and aircraft carriers. A Director General of Recruiting is appointed. Two infantry battalions of British Expeditionary Force 50th Division and 1st Army Tank Brigade attack German forces southeast of Arras, with 58 Mark I Matilda tanks (with single machine guns), and 16 Mark II Matilda tanks (with high-velocity 40-mm guns). They inflict serious casualties on Erwin Rommel's artillery and infantry, until Rommel forms a defensive line of artillery and 88-mm anti-aircraft guns. This line destroys 36 British tanks. Panzer tanks join in destroying a further seven tanks, but at a loss of three Panzer IV tanks, six Panzer III tanks, and other light tanks. German troop losses total 387 men in this one battle, four times the total losses to date. (Possibly because of this loss of tanks and men, on May 24 Adolf Hitler orders all panzers to halt for three days, allowing a massive British evacuation at Dunkirk.)
22 May 1940	German panzers head north along the coast from Abbéville.
23 May 1940	German Ju87 Stuka planes attack and sink British destroyer Kashmir during the Battle of Crete. British destroyer Kelly is sunk during the Battle of Crete. Boulogne, France, falls to German troops. German forces set siege to Calais, France.
24 May 1940	King Léopold of Belgium informs four Government ministers he would stay with the Army in Belgium, capitulating to the Germans if necessary. Royal Canadian Navy destroyers Restigouche, St. Laurent, Skeena, and Fraser head to the United Kingdom to aid the Royal Navy. Adolf Hitler orders Walther von Brauchitsch, army commander in chief, to halt the panzers along the Bassée Canal, specifically to remain at medium artillery range from Dunkirk. German Army Group A Commander Field Marshal Gerd von Rundstedt begins issuing orders for his panzer tank divisions to halt their advance in France, due to losses and maintenance problems. The Allied Expeditionary Force withdraws completely from Norway. Adolf Hitler issues Directive No. 13. The objective is to annihilate French, English, and Belgian forces surrounded in Artois and Flanders. The Air Force is to prevent the escape of English forces across the Channel. The Air Force is authorized to attack England to the fullest when sufficient forces are available.
25 May 1940	The British Chiefs of Staff present a report to the War Cabinet entitled "British Strategy in a Certain Eventuality". If France collapses and German forces invade Great Britain, it is unlikely Britain could send naval forces to Singapore. In the event, the USA would have to be relied on to safeguard British interests in the Far East. In France, British commander John Gort cancels a planned advance to the south, and orders his troops north, so they could embark for England.
25 May 1940	Adolf Hitler lifts his panzer halt order. Army headquarters directs panzers to move south to attack across the Somme River. German forces take Boulogne and Calais, France. Wilhelm Keitel issues an order for the German Air Force to attack British food supplies, public services, and aircraft industry. A British order is given to implement Operation Dynamo, for British destroyers to rescue up to 4500 men of the British Expeditionary Force from Dunkirk, France, within two days.
27 May 1940	Evacuation of Allied troops begins, from Dunkirk, France, across the English Channel. German forces in France begin their advance again. The British War Cabinet approves the view of the Chiefs of Staff that Britain and the Commonwealth nations alone could produce a crisis in Germany by the middle of 1941. Belgian King Léopold decides to cease resistance to the German army. Belgian General Deroussaux approaches the German army under a flag of truce, to learn the terms of a cease-fire. Weygand and Premier Paul Reynaud in Paris receive warning from King Léopold of Belgium that his Army would soon be forced to capitulate.
28 May 1940	King Leopold III of Belgium surrenders the army unconditionally to German forces. French 4th Armored Division forces the retreat of a German armored division at Caumont. This makes commander Colonel Charles de Gaulle the first and only French Commanding Officer to force a German retreat during the invasion of France. French General Béthouart leads a force from Bjerkvik on Narvik, Norway. Polish troops attack Narvik, Norway, from south of the village. Allied troops complete taking Narvik, Norway.
29 May 1940	About 40 miles north-west of La Panne, France, British destroyer Wakeful is hit by a torpedo, splits in half, and sinks in 15 seconds, killing about 100 soldiers. In the English Channel, German submarine U69 torpedoes British destroyer Grafton, also damaging destroyer Comfort. British destroyer Lydd rams Comfort in error, cutting the ship in half. In the English Channel, British destroyer Gallant strikes a mine, killing 55 of the crew, but the ship survives.   Off Dunkirk, France, British destroyer Grenade is bombed and sunk.
30 May 1940	Belgian Ministers hold a Cabinet meeting in Limoges, France. They declare that it is impossible for the King to reign, due to being under the power of German invaders. British Prime Minister Winston Churchill orders that British and French soldiers be evacuated from Dunkirk in equal numbers.
31 May 1940	Total German submarine sinkings of merchant shipping in the Atlantic during the past three months: 43 ships, 140,000 tons.