1941

Events

January

• January–August - 10,072 men, women and children with mental and physical disabilities are asphyxiated with carbon monoxide in a gas chamber, at Hadamar Euthanasia Centre in Germany, in the first phase of mass killings under the Aktion T4 program here.
• January 1 - Thailand's Prime Minister Plaek Phibunsongkhram decrees January 1 as the official start of the Thai solar calendar new year.
• January 3 - A decree promulgated in Germany by Martin Bormann, on behalf of Adolf Hitler, requires replacement of blackletter typefaces by Antiqua.
• January 4 - The short subject Elmer's Pet Rabbit is released, marking the second appearance of Bugs Bunny, and also the first to have his name on a title card.
• January 5 - WWII: Battle of Bardia in Libya: Australian and British troops defeat Italian forces, the first battle of the war in which an Australian Army formation takes part.
• January 6
• * During his State of the Union address, President of the United States Franklin D. Roosevelt presents his Four Freedoms, as fundamental global human rights.
• * The keel of battleship is laid at the New York Navy Yard in Brooklyn.
• January 10 - The Lend-Lease Act is introduced into the United States Congress.
• January 11 - WWII: The British Royal Navy light cruiser is bombed, catches fire and has to be sunk off Malta, with the loss of 81 crew.
• January 13 - All persons born in Puerto Rico since this day are declared U.S. citizens by birth, through U.S. federal law.
• January 14
• * WWII: Commerce raiding German auxiliary cruiser Pinguin captures the Norwegian whaling fleet near Bouvet Island, effectively ending Southern Ocean whaling for the duration of the war.
• * In a BBC radio broadcast from London, Victor de Laveleye asks all Belgians to use the letter "V" as a rallying sign, being the first letter of victoire in French and of vrijheid in Dutch. This is the beginning of the "V campaign" which sees "V" graffities on the walls of Belgium and later all of Europe and introduces the use of the "V sign" for victory and freedom. Winston Churchill adopts the sign soon afterwards, though he sometimes gets it the wrong way around and uses the common insult gesture.
• January 15 - John Vincent Atanasoff and Clifford Berry describe the workings of the Atanasoff–Berry computer in print.
• January 19 - WWII: British troops attack Italian-held Eritrea in Africa.
• January 22
• * WWII: Battle of Tobruk: Australian and British forces capture Tobruk from the Italians.
• * In Sweden, Victor Hasselblad registers the Hasselblad Camera Company.
• January 23 - Aviator Charles Lindbergh testifies before the U.S. Congress, and recommends that the United States negotiate a neutrality pact with Adolf Hitler.
• January 27 - WWII: Joseph Grew, the U.S. ambassador to Japan, reports to Washington a rumor overheard at a diplomatic reception, concerning a planned surprise attack on Pearl Harbor, Hawaii.
• January 28 - Subhas Chandra Bose, the chief of the separatist Indian National Army, reaches Kabul, Afghanistan by successfully evading the British authorities in British India.
• January 30 - WWII: Australians capture Derna, Libya, from the Italians.

  February

• February 3 - WWII: The Nazis forcibly restore Pierre Laval to the office of Prime Minister in occupied Vichy France.
• February 4 - WWII: The United Service Organization is created to entertain American troops.
• February 5 - The Air Training Corps is formed in the United Kingdom.
• February 5–April 1 - WWII: Battle of Keren - British and Free French Forces fight hard to capture the strategic town of Keren in Italian Eritrea.
• February 6 - WWII: Benghazi falls to the British Western Desert Force. Lieutenant-General Erwin Rommel is appointed commander of Afrika Korps.
• February 8 - WWII: The U.S. House of Representatives passes the Lend-Lease Act.
• February 9 - Winston Churchill, in a worldwide broadcast, tells the United States to show its support by sending arms to the British: "Give us the tools, and we will finish the job."
• February 12
• * WWII: Erwin Rommel arrives in Tripoli.
• * Reserve Constable Albert Alexander, a patient at the Radcliffe Infirmary in Oxford, England, becomes the first person treated with penicillin intravenously, by Howard Florey's team. He reacts positively, but there is insufficient supply of the drug to reverse his terminal infection. A successful treatment is achieved during May.
• February 13 - Aircraft from British carrier attack Massawa in Eritrea.
• February 14 - WWII: Admiral Kichisaburō Nomura begins his duties as Japanese Ambassador to the United States.
• February 19–22 - WWII: Three Nights' Blitz over Swansea, South Wales: Over these 3 nights of intensive bombing, which lasts a total of 13 hours and 48 minutes, Swansea's town centre is almost completely obliterated by the 896 high explosive bombs employed by the Luftwaffe; 397 casualties and 230 deaths are reported.
• February 22 - WWII: British cruiser bombards Barawa, on the coast between Kismayo and Mogadishu.
• February 23 - Glenn T. Seaborg and associates isolate and discover plutonium, at the University of California, Berkeley.
• February 25 - WWII:
• * The occupied Netherlands starts the first popular uprising in Europe against the Axis powers, the "February strike" against German deportation of Jews in Amsterdam and surroundings.
• * British submarine attacks an Italian convoy, sinking the cruiser Armando Diaz.
• February 27 - WWII: The New Zealand Division cruiser HMS Leander sinks Italian armed merchant raider Ramb I off the Maldives.

  March

• March 1
• * WWII: Bulgaria signs the Tripartite Pact, thus joining the Axis powers.
• * Arthur L. Bristol becomes Rear Admiral for the United States Navy's Support Force, Atlantic Fleet.
• March 4 - WWII: Operation Claymore - British Commandos carry out a successful raid on the Lofoten Islands, off the north coast of Norway.
• March 5 - Franklin D. Roosevelt, having been President of the United States for 8 years, 1 day, becomes the longest-serving president in American history.
• March 11 - WWII: Franklin D. Roosevelt, President of the United States, signs the Lend-Lease Act into law, providing for the U.S. to provide Lend-Lease aid to the Allies.
• March 15 - Berlin-based American journalist Richard C. Hottelet is arrested by the Gestapo on "suspicion of espionage", but eventually released in July as part of a prisoner exchange with the U.S.
• March 16 - A group of U.S. warships arrive in Auckland, New Zealand, on a goodwill visit. On March 20, they arrive in Sydney, Australia.
• March 17
• * In Washington, D.C., the National Gallery of Art is officially opened by President Franklin D. Roosevelt.
• * British Minister of Labour Ernest Bevin calls for women to fill vital jobs.
• March 22 - Washington state's Grand Coulee Dam begins to generate electricity.
• March 24 - WWII: Rommel launches his first offensive in Cyrenaica.
• March 25 - WWII: The Kingdom of Yugoslavia joins the Axis powers in Vienna.
• March 27 - WWII:
• * Battle of Cape Matapan: Off the Peloponnese coast in the Mediterranean, British naval forces defeat those of Italy, sinking 5 warships.
• * Yugoslav coup d'état: An anti-Axis coup d'état in the Kingdom of Yugoslavia led by General Dušan Simović, Brigadier General Borivoje Mirković, Colonels Dragutin Savić and Stjepan Burazović, Colonel General Miodrag Lazić, Milorad Petrović and many other general officers forces Prince Paul into exile; 17-year-old King Peter II assumes power following the coup and Simović is elected new Prime Minister of Yugoslavia.
• * Japanese spy Takeo Yoshikawa arrives in Honolulu to study the United States Pacific Fleet at Pearl Harbor, in preparation for a future attack.
• March 30 - WWII:
• * All German, Italian and Danish ships anchored in United States waters are taken into "protective custody".
• * A German Lorenz cipher machine operator sends a 4,000-character message twice, allowing British mathematician Bill Tutte to decipher the machine's coding mechanism.

  April

• April - The Valley of Geysers is discovered on the Kamchatka Peninsula of Russia, by Tatyana Ustinova.
• April 1 - A military coup d'état, launched by Rashid Ali Al-Gaylani, overthrows the pro-British regime in Iraq.
• April 4 - WWII: Axis forces capture Benghazi.
• April 6 - WWII: Germany, Italy and Hungary invade Yugoslavia and the Battle of Greece begins.
• April 9 - The U.S. acquires full military defense rights in Greenland.
• April 10 - WWII:
• * U.S. destroyer, while picking up survivors from a sunken Dutch freighter, drops depth charges on a German U-boat.
• * The Independent State of Croatia, a puppet state of the Axis powers, is established with Ustashe leader Ante Pavelić as head of the government.
• April 12 - WWII: German troops enter Belgrade.
• April 13 - The Soviet–Japanese Neutrality Pact is signed.
• April 15 - WWII: Axis forces reach Halfaya Pass, on the Libyan-Egyptian frontier.
• April 17 – WWII: Yugoslavia capitulates after the joint Axis invasion of the country results in the bombing of Belgrade.
• April 18 - WWII: Greek Prime Minister Alexandros Koryzis commits suicide as German troops approach Athens.
• April 19 - Bertolt Brecht's anti-war play Mother Courage and Her Children receives its first theatrical production, at the Schauspielhaus Zürich.
• April 21 - WWII: Greece capitulates to Germany. Commonwealth troops and some elements of the Greek Army withdraw to Crete.
• April 23 - The America First Committee holds its first mass rally in New York City, with Charles Lindbergh as keynote speaker.
• April 25 - Franklin D. Roosevelt, at his regular press conference, criticizes Charles Lindbergh by comparing him to the Copperheads of the Civil War period. In response, Lindbergh resigns his commission in the U.S. Army Air Corps Reserve on April 28.
• April 27 - WWII: German troops enter Athens.
• April 28 - World War II persecution of Serbs: Gudovac massacre - Members of the Croatian nationalist Ustashe movement kill around 190 Bjelovar Serbs in the village of Gudovac, in the Independent State of Croatia.