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Wikimedia Commons has media related to . 1942 1942 ( MCMXLII) was a common year starting on Thursday of the Gregorian calendar, the 1942nd year of the Common Era (CE) and (AD) designations, the 942nd year of the Anno Domini 2nd millennium, the 42nd year of the 20th century, and the 3rd year of the 1940s decade.
Along with this, 1942 was when
Nazi Germany reached its peak dominance in the Northern European war front, under the command of Adolf Hitler.
Below, the events of
World War II have the "WWII" prefix.
Map of Europe at the height of German control in 1942, Britain remains the only country in Western Europe held by Allied forces
February 1 – WWII:
February 3 – WWII: Rommel suspends his offensive in Cyrenaica.
February 7 – United States Maritime Commission fleet operations are transferred to the War Shipping Administration (lasting until September 1, 1946).
António Óscar Carmona is elected president of Portugal. WWII: the Top United States military leaders hold their first formal meeting, to discuss American military strategy in the war.
Daylight saving time goes into effect in the United States.
February 9 – The ocean liner SS catches fire while being converted into the troopship USS Normandie Lafayette (AP-53) for WWII at Pier 88 in New York City; she capsizes early the following morning.
February 11 – Operation Cerberus: A flotilla of Kriegsmarine ships dash from Brest through the English Channel to northern ports; the British fail to sink any of them.
February 15 – WWII: Battle of Singapore – Singapore surrenders to Japanese forces.
February 18 – WWII:
February 19 – WWII:
February 19– 23 – WWII: Battle of Sittang Bridge – British forces retreat to the Sittaung River.
February 20 – WWII: Lieutenant Edward O'Hare becomes America's first U.S. Navy flying ace of the war.
February 22 – WWII: General George Marshall transmits a direct order to General MacArthur in President Roosevelt's name, ordering MacArthur himself to turn over command of the Philippines to a subordinate, and report to Australia to assume command of the large American force being built up there. The orders are worded to allow MacArthur to choose the exact moment of his departure; for various reasons, he will not leave until March 11.
February 23 – WWII: Japanese submarine fires 17 high-explosive shells toward an I-17 oil refinery near Santa Barbara, California, causing little damage.
February 25 – " Battle of Los Angeles": Over 1,400 AA shells are fired at an unidentified, slow-moving object (probably a meteorological balloon) in the skies over Los Angeles. The appearance of the object triggers an immediate wartime blackout over most of Southern California, with thousands of air raid wardens being deployed throughout the city. At least 5 deaths are related to the incident. Despite the several hour barrages no planes are downed.
February 27 – WWII: Battle of the Java Sea: An allied ( ABDA) task force of 14 vessels under Dutch command, trying to stem a Japanese invasion of the Dutch East Indies, is defeated by a 19-vessel Japanese task force in the Java Sea; 2.300 sailors die, including the commander, Admiral Karel Doorman; Japanese attain naval hegemony in East-Asia.
March – Construction begins on the Badger Army Ammunition Plant, the largest in the United States during WWII.
March 6 – Yugoslav Partisans, operating in Nazi-occupied Serbia, assassinate Đorđe Kosmajac in Belgrade.
March 9 – WWII: Executive order 9082 (February 28, 1942) comes into effect, reorganizing the United States Army into three major commands: Army Ground Forces, Army Air Forces, and Services of Supply, later redesignated Army Service Forces, with Henry H. Arnold as Commanding General of the United States Army Air Forces.
March 11 – WWII: Douglas MacArthur's escape from the Philippines – U.S. General Douglas MacArthur, his family and key members of his staff are evacuated by PT boat, under cover of evening darkness, from Corregidor in the Philippines. Command of U.S. forces in the Philippines passes to Major General Jonathan M. Wainwright.
March 15 – WWII: Dünamünde Action: 1,900 central European Jews are shot dead north east of Riga, 1,840 are killed on the 26th.
March 16 – WWII: New Zealand and Australia declare war on Thailand.
March 17 – The Holocaust: Operation Reinhard – The Nazi German Bełżec extermination camp opens in occupied Poland, about 1 km south of the railroad station at Bełżec in the Lublin district of the General Government. At least 434,508 people are killed here up to December 1942.
March 18 – Franklin D. Roosevelt, President of the United States, signs Executive Order 9102, creating the War Relocation Authority (WRA), which becomes responsible for the internment of Americans of Japanese and, to a lesser extent, German and Italian descent, many of them legal citizens.
March 20 – WWII: After being forced to flee the Philippines, U.S. General Douglas MacArthur announces (in Terowie, South Australia), "I came through and I shall return." 
March 22 – WWII: Second Battle of Sirte in the Mediterranean Sea – Escorting warships of a British convoy to Malta ward off a much more powerful (Italian Navy) squadron, north of the Regia Marina Gulf of Sirte.
March 23 – WWII: The Germans burn down the Ukrainian village of Yelino ( Koriukivka Raion), killing 296 civilians. 
March 24 – The evacuation of Polish nationals from the Soviet Union begins. It is conducted in two phases: until April 5; and between August 10 and 30, 1942, by sea from Krasnovodsk to Pahlavi (Anzali), and (to a lesser extent) overland from Ashkabad to Mashhad. In all, 115,000 people are evacuated, 37,000 of them civilians, 18,000 children (7% of the number of Polish citizens originally exiled to the Soviet Union). 
March 25– 26 – The Holocaust: First mass transport of Jews to Auschwitz concentration camp, 997 women and girls from Poprad transit camp in the Slovak Republic.
March 28 – WWII:
March 29 – WWII: Following a coup d'état, the Free Republic of Nias is proclaimed by a group of freed Nazi German prisoners in the Indonesian island of Nias; the republic exists for less than a month until the island is fully occupied by Japanese troops. March 31 – WWII: Battle of Christmas Island – Japanese troops occupy Christmas Island without resistance, following a mutiny by British Indian Army troops against their British officers.
April 3 – WWII: Japanese forces begin the last phase of the Battle of Bataan, an all-out assault on the United States and Filipino troops on the Bataan Peninsula.
April 5 – WWII: Easter Sunday Raid – Aircraft of the Japanese Navy attack Colombo, Ceylon ( Sri Lanka). Royal Navy cruisers HMS and Cornwall HMS are sunk southwest of the island. Dorsetshire
April 9 – WWII:
April 10 – The Holocaust: Construction of the Nazi German extermination camp Treblinka II commences in occupied Poland near the village of Treblinka. Between July 23, 1942, and October 1943, around 850,000 people are killed here, more than 800,000 of whom are Jews.  
April 12 – Disney's is released in Bambi theaters everywhere.
April 13 – The United States Federal Communications Commission's minimum programming time required of television stations is cut from 15 hours to 4 hours a week during the war.
April 15 – WWII: Award of the George Cross to Malta: King George VI awards the George Cross to the island of Malta to mark the Siege of Malta, saying, "To honor her brave people I award the George Cross to the Island Fortress of Malta, to bear witness to a heroism and a devotion that will long be famous in history" (from January 1 to July 24, there is only one 24-hour period during which no bombs fall on this tiny island).
April 17 – WWII: Henri Giraud, the French commander captured in 1940, escapes from Königstein Fortress.
April 18 – WWII: Doolittle Raid: A small force of B-25 Mitchell bomber aircraft, commanded by then-Lieutenant Colonel James "Jimmy" Doolittle bomb Tokyo, Japan.
April 25 – Princess Elizabeth registers for war service in the U.K.
Reichstag meets for the last time, dissolving itself and proclaiming Adolf Hitler the "Supreme Judge of the German People", granting him the power of life and death over every German citizen. A gas and coal dust explosion at Benxihu Colliery in Manchukuo kills as many as 1,549 workers, the world's all-time worst mining disaster.
national plebiscite is held in Canada on the issue of conscription. The Jewish Star of David is required wearing for all Jews in the Netherlands and Belgium; Jews in other Nazi-controlled countries have already been wearing it. April 29 – WWII: An explosion at a chemical factory in Tessenderlo, Belgium leaves 200 dead and 1,000 injured.
May – Operation Pluto: The plan to construct oil pipelines under the English Channel, between England and France, is tested in the River Medway.
May 3– 4 – WWII: Tulagi is invaded by Japanese forces in the British Solomon Islands of the South Pacific, as part of Operation Mo.
May 5 – WWII: Battle of Madagascar (Operation Ironclad) begins when British forces land on the Vichy French colony of Madagascar. On May 7 the northern city of Diego Suarez surrenders.
May 7 – WWII: On Corregidor, the last American and Filipino forces in the Philippines under command of 2LT Robert L. Obourn ( 92nd Coast Artillery Regiment, G Battery) from Fort Mills, surrender to the Japanese as directed by Lt. Gen. Jonathan M. Wainwright, the overall commander.  
May 8 – WWII:
May 8/ 9 – WWII: At night, gunners of the Ceylon Garrison Artillery on Horsburgh Island in the Cocos Islands mutiny. The mutiny is crushed, and 3 soldiers are executed (the only British Commonwealth soldiers to be executed for mutiny during the Second World War).
May 12 – WWII:
May 14 – Aaron Copland's is performed for the first time, by the Lincoln Portrait Cincinnati Symphony Orchestra.
May 15 – WWII: In the United States, a bill creating the Women's Auxiliary Army Corps (WAAC) is signed into law.
May 20 – The first African-American seamen are taken into the United States Navy.
May 21 – WWII: Mexico declares war against Nazi Germany, after the sinking of the Mexican tanker by Faja de Oro German submarine off U-160 Key West.
May 26 – WWII:
May 27 – WWII: Operation Anthropoid: Czech paratroopers attempt to assassinate Reinhard Heydrich in Prague, and succeed in wounding him.
May 29 – Thai spelling reform of 1942 is initiated by the government of Prime Minister Field Marshal Plaek Phibunsongkhram with his office announcing a simplification of the Thai alphabet. The announcement is published in the Royal Gazette on June 1. The reform is canceled by the government of Khuang Aphaiwong on August 2, 1944.
May 30– 31 – WWII: Bombing of Cologne – British RAF Bomber Command's "Operation Millennium", its first "1,000 bomber raid", with associated fires make 13,000 families homeless and kills around 475 people, mostly civilians; 3,330 non-residential buildings are destroyed. May 31– June 1 – WWII: Attack on Sydney Harbour: Japanese midget submarines infiltrate Sydney Harbour in Australia, in an attempt to attack Allied warships.
June 4 – WWII: Reinhard Heydrich succumbs to wounds sustained on May 27, from Czechoslovakian paratroopers acting in Operation Anthropoid.
June 5 – The United States declares war on Bulgaria, Hungary and Romania.
June 4– June 7 – WWII: Battle of Midway: The Japanese naval advance in the Pacific is halted.
June 7 – WWII: Japanese forces invade the Aleutian Islands (the first invasion of American soil in 128 years).
June 8 – WWII: Attack on Sydney Harbour: The Australian cities of Sydney and Newcastle are shelled by Japanese submarines. The eastern suburbs of both cities are damaged, and the east coast is blacked out.
June 9 – WWII: Nazis burn the Czech village of Lidice, in reprisal for the killing of Reinhard Heydrich.
June 10 – WWII: The Gestapo massacres 173 male residents of Lidice, Czechoslovakia in retaliation for the killing of Reinhard Heydrich.
June 12 – The Holocaust: On her 13th birthday, Anne Frank makes the first entry in her new diary.
June 13 – WWII: The United States opens its Office of War Information, a propaganda center.
June 18 – WWII: The SS surrounds the church where Jan Kubiš and Jozef Gabčík, the assassins of Reinhard Heydrich, are hiding. Kubiš is fatally wounded in the ensuing shootout, and Gabčík commits suicide to avoid capture.
June 23 – The experimental early-type nuclear reactor L-IV has an accident, becoming the first nuclear accident in history and consisting of a steam explosion and reactor fire in Leipzig.
June 28 – WWII: The Germans launch Case Blue, Army Group South's drive to Stalingrad and the Baku Oil fields. June 29 – WWII: The German Eleventh Army under Erich von Manstein takes Sevastopol, although fighting rages until July 9.
July – The Holocaust: Inmates of Westerbork transit camp in the occupied Netherlands begin to be shipped to Nazi extermination camps. From now until 1944 around 107,000, mostly Jewish, from here will be killed.
July 1– July 27 – WWII: First Battle of El Alamein: British forces prevent a second advance by Axis forces into Egypt.
July 3 – WWII: Guadalcanal, occupied only by aborigines, falls to the Japanese Naval construction force deployed to construct an airfield on the island.
July 4 – WWII in the European Theater of Operations:
Twenty-four ships are sunk by German bombers and submarines after
Convoy PQ 17 to the Soviet Union is scattered in the Arctic Ocean to evade the German battleship . Tirpitz The United States Eighth Air Force inauspiciously flies its first mission in Europe, using borrowed British planes, and bombs targets in the Netherlands, such as De Kooy Airfield, attached to the Den Helder Naval Base. Three of six aircraft return; For this mission, Captain Charles C. Kegelman is the first member of the Force to be awarded the U.S.  Distinguished Flying Cross. 
July 6 – The Holocaust: Anne Frank's family goes into hiding in an attic above her father's office in an Amsterdam warehouse.
July 8 – Turkish prime minister Refik Saydam dies while working in the office. For one day he is succeeded by Ahmet Fikri Tüzer.
July 9 – Şükrü Saracoğlu forms the new (13th) government in Turkey.
July 10 – Americans find a Japanese Mitsubishi A6M Zero aircraft, dubbed the Akutan Zero, which provides critical military information for Allied forces.
July 13 – WWII: U-boats sink 3 more merchant ships in the Gulf of St. Lawrence.
July 14 – WWII:
July 18 – WWII: The Germans test fly the Messerschmitt Me 262 (using only its jet engines) for the first time.
July 19 – WWII: Battle of the Atlantic: German Grand Admiral Karl Dönitz orders the last U-boats to withdraw from there the United States Atlantic coast positions, in response to an effective American convoy system.
July 21 – WWII: The Japanese establish a beachhead on the north coast of New Guinea in the Buna-Gona area; a small Australian force begins a rearguard action on the Kokoda Track campaign.
July 22 – The Holocaust: The systematic deportation of Jews from the Warsaw Ghetto begins. 
July 23 – The Holocaust: The gas chambers at Treblinka extermination camp begin operation, killing 6,500 Jews newly arrived from the Warsaw Ghetto.
July 29 – The Presidium of the Supreme Soviet of the Soviet Union institutes the Order of Suvorov and Order of Kutuzov and reinstates the Order of Alexander Nevsky.
July 30 – WWII:
WAVES (Women Accepted for Volunteer Emergency Service), the United States Naval Reserve (Women's Reserve), is signed into law. The SS is sunk in the Robert E. Lee Gulf of Mexico by , which is itself sunk by the escorting patrol craft. U-166 July 31 – The Oxford Committee for Famine Relief (Oxfam) is founded in England.
August 4 – WWII: Operation Letica: An assassination attempt on Serbian fascist Minister of Finance Dušan Letica, by a group Yugoslav Resistance fighters, fails.
August 7 – WWII: Guadalcanal Campaign – The U.S. Navy and the U.S. Marine Corps begin the first American offensive of the war, with an amphibious landing on the island of Guadalcanal in the Solomon Islands.
WWII: Allied North Atlantic
convoy SC 94 loses 10 ships, as the first to be heavily attacked by U-boats resuming mid-Atlantic wolf pack attacks, through the climactic winter of 1942/43.  WWII: In Washington, D.C., six German
saboteurs are executed for their role in the failed mission Operation Pastorius (2 others are cooperative and receive sentences of life imprisonment instead, being freed a few years after the end of the war). WWII: Battle of Savo island: Japanese Imperial Navy attacked US Navy off Savo Island, north of Guadalcanal. Japanese victory forced admiral Fletcher to withdraw US naval support leaving the Marines on Guadalcanal isolated. However, the Japanese commander vice admiral Gunichi Mikawa, fearing exposure to daylight attack by US aircraft from nearby US navy aircraft carriers, withdrew before daybreak the following morning of August 9th, failing to destroy the US Marine transports and supplies.
August 11 – Hedy Lamarr's and her friend George Antheil's frequency-hopping system for radio-controlled torpedoes is granted a patent under US Patent 2,292,387. In 1962 (at the time of the Cuban missile crisis), an updated version of their design will at last appear on Navy ships.  
August 13 – A Quit India resolution is passed by the Bombay session of the All India Congress Committee (AICC), which leads to the start of a historical civil disobedience movement across India.
August 15 – WWII: American tanker reaches Malta, as part of the convoy of Ohio . Operation Pedestal
August 17 – WWII: Heavy bombers of the U.S. Eighth Air Force, based in England, conduct their first raid against occupied France.
August 19 – WWII: Dieppe Raid: Allied forces raid Dieppe, France.
August 20 – Plutonium is isolated for the first time, at the Metallurgical Laboratory of the University of Chicago.
August 21 – WWII: Battle of the Tenaru: Allies defeat Japanese land forces on Guadalcanal.
August 22 – WWII: Brazil declares war on Germany and Italy.
August 23 – WWII: Battle of Stalingrad begins: German troops reach the suburbs of Stalingrad.
August 27– 28 – Sarny Massacre: Nazi troops and the Ukrainian Auxiliary Police systematically execute more than 14,000 people, mostly Jews, in and around Sarny in German-occupied Poland.
August 28 – Polish writer Zofia Kossak-Szczucka, as head of the underground organization Front for the Rebirth of Poland, publishes in Warsaw her Protest! against the mass murder of Jews in German-occupied Poland.
August 30 – Luxembourg is formally annexed to the German Reich.
August 30– September 5 – WWII: Battle of Alam el Halfa – British forces in the Western Desert resist a German attack. August 31 – The 1942 Luxembourgish general strike is launched, to protest against forced conscription in Luxembourg.
September 2 – The island of Les Casquets in the Channel Islands is raided by the forerunner of the British SAS, the SSRF, led by Major Gus March-Phillipps; this is one of the first raids by Anders Lassen VC. In the raid, the entire garrison of 7 is abducted and returned to England as prisoners, and the radio and lighthouse wrecked.  
September 3 – The Holocaust: A German attempt to liquidate the Jewish Łachwa Ghetto in occupied Poland leads to an uprising, probably the first ghetto uprising of the war.
September 9 – WWII: A Japanese floatplane drops incendiary devices at Mount Emily, near Brookings, Oregon, in the first of two " Lookout Air Raids", the first bombing of the continental United States.
September 12 – The RMS , carrying civilians, Allied soldiers, and Italian prisoners of war, is torpedoed off the coast of West Africa and sinks, killing 1,649 people. Laconia
September 15 – The Women's Flying Training Detachment (WFTD) is established in the United States.
September 24 – WWII: Andrée Borrel and Lise de Baissac become the first female SOE agents to be parachuted into occupied France.
September 26 – The Holocaust: Nazi official August Frank issues the August Frank memorandum, setting out how the belongings of "evacuated" (i.e. murdered) Jews are to be disposed of. September 27 – WWII: Both the commerce raiding German auxiliary cruiser and American Stier Liberty ship SS sink, following a gun battle in the South Atlantic. Stephen Hopkins Hilfskreuzer Stier is the only commerce raider to be sunk by a defensively equipped merchant ship. 
HMS collides with liner Curacoa RMS (carrying troops from the United States) off the coast of Queen Mary Donegal and sinks; 338 drown. WWII: Japanese troopship sinks, following a torpedo attack the previous day by submarine Lisbon Maru USS off the coast of China; 829 are killed, mostly British prisoners of war who (unknown to the attacker) were being held on board. Grouper
October 3 – The first A-4 rocket is successfully launched from Test Stand VII at Peenemünde, Germany. The rocket flies 147 kilometers and reaches an altitude of 84.5 kilometers, becoming the first man-made object to reach space.
October 11 – WWII: Battle of Cape Esperance: On the northwest coast of Guadalcanal, United States Navy ships intercept and defeat a Japanese fleet, on their way to reinforce troops on the island.
October 13 – WWII: North Atlantic convoy SC 104 is attacked by U-boats, sinking seven ships. 
cyclone and consequential floods in the Bay of Bengal kill 40,000 people, with particularly heavy damage around Contai.  Animated short film The Mouse of Tomorrow, featuring the debut of Mighty Mouse (as "Super Mouse"), is released in the United States.
October 18 – WWII: Hitler issues the Commando Order, which stipulates that all Allied commandos encountered by German forces should be executed immediately without trial, even in proper uniforms, in response to the Dieppe Raid and Operation Basalt conducted by the Allies. After the war, the Nuremberg trials finds this order a direct violation of the laws and customs of war.
October 21 – A Royal New Zealand Air Force torpedo bomber sinks the German MS , with a loss of 946 lives. Palatia
October 23 – Award-winning composer and songwriter Ralph Rainger ("Thanks for the Memory") is among 12 people killed in a mid-air collision between an American Airlines DC-3 and a U.S. Army bomber near Palm Springs, California.
October 23– 26 – WWII: Battle for Henderson Field: Japanese forces fail to recapture Henderson Field airfield in Guadalcanal from the Americans.
October 23– November 4 – WWII: Second Battle of El Alamein: British troops go on the offensive against the Axis forces.
October 26 – WWII: Battle of the Santa Cruz Islands: Two Japanese aircraft carriers are heavily damaged and one U.S. Navy carrier is sunk.
October 29 – The Holocaust: In the United Kingdom, leading clergymen and political figures hold a public meeting to register outrage over Nazi Germany's persecution of Jews. October 30 – WWII:
November 1 – WWII: North Atlantic convoy SC 107 is heavily attacked by U-boats, sinking 15 ships. 
November 2 – A USAAF squadron, including B-24 Liberators, intercepts many Luftwaffe patrols off the coast of Oran, Algeria.
November 3 – WWII: Second Battle of El Alamein: German forces under Erwin Rommel are forced to retreat during the night.
November 6 – WWII: Battle of Madagascar ends when Vichy French forces on Madagascar sign an armistice with the Allies.
November 8 – WWII:
Operation Torch: the United States and the United Kingdom forces land in French North Africa. French Resistance Coup in Algiers: 400 French civil resisters neutralize the Vichyist XIXth Army Corps and the Vichyist generals (Juin, Darlan, etc.), thus allowing the immediate success of Operation Torch in Algiers, and ultimately the whole of French North Africa.
November 9 – WWII: U.S. serviceman Edward Leonski is hanged at Melbourne's Pentridge Prison, for the "Brown-Out" murders of three women in May.
November 10 – WWII: In violation of a 1940 armistice, Germany invades Vichy France, following French Admiral François Darlan's agreement to an armistice with the Allies in North Africa.
November 12 – WWII: Guadalcanal Campaign: A naval battle near Guadalcanal starts between Japanese and American forces.
November 13 – WWII:
November 15 – WWII:
November 18 – WWII: North Atlantic convoy ON 144 is attacked by U-boats, sinking 5 ships. 
November 19 – WWII: Battle of Stalingrad: Soviet Union forces under General Georgy Zhukov launch the Operation Uranus counter-attacks at Stalingrad, turning the tide of the battle in the USSR's favor.
November 20 – WWII: British forces capture Benghazi.
November 21 – The completion of the Alaska Highway (also known as the Alcan Highway) is celebrated (however, the " highway" is not usable by general vehicles until 1943).
November 22 – WWII: Battle of Stalingrad: The situation for the German attackers of Stalingrad seems desperate during the Soviet counter-attack Operation Uranus, and General Friedrich Paulus sends Adolf Hitler a telegram, saying that the German Sixth Army is surrounded.
November 23 – WWII
U-boat sinks the SS off the coast of Brazil. One crewman, Chinese second steward Benlomond Poon Lim, is separated from the others and spends 130 days adrift, until he is rescued on April 3, 1943. Legislation approves the United States Coast Guard Women's Reserve, to help fill jobs and free men to serve during the war effort. They are known as the SPARS ("Semper Paratus, Always Ready!")
November 25– 26 – WWII: Operation Harling: A British Special Operations Executive team, together with Greek Resistance fighters, blows up the Gorgopotamos viaduct, in the first major sabotage act in occupied continental Europe.
November 26 – The movie premières at the Hollywood Theater in New York City. Casablanca
November 27 – WWII: At Toulon, the French navy scuttles its ships and submarines, to keep them out of Nazi hands.
November 29 – The Blue Star Line cargo liner MV runs aground on the Dunedin Star Skeleton Coast of Namibia. Crew and passengers survive, following a 26-day overland trek to Windhoek.  November 30 – WWII: Battle of Tassafaronga – In a nighttime naval battle as part of the Guadalcanal Campaign, ships of the Imperial Japanese Navy defeat those of the United States Navy.
December 1 – Gasoline rationing begins in the United States.
December 2 – Manhattan Project: Below the bleachers of Stagg Field at the University of Chicago, a team led by Enrico Fermi initiates the first self-sustaining nuclear chain reaction (a coded message, "The Italian navigator has landed in the new world" is then sent to U.S. President Franklin D. Roosevelt).
The Holocaust: In Warsaw, two women, Zofia Kossak and Wanda Filipowicz, risk their lives by setting up the Council for the Assistance of the Jews. WWII: USAAF bombers make their first raid on Italy.
December 6 – Stary Ciepielów and Rekówka massacre: 5 families in Occupied Poland are executed by the as part of the Ordnungspolizei German retribution against Poles who helped Jews.
December 7 – WWII:
December 8 – A fire at Seacliff Lunatic Asylum in New Zealand kills 39 patients.
December 10 – The Holocaust: The Polish government-in-exile sends copies of , including The Mass Extermination of Jews in German Occupied Poland Raczyński's Note, the first official report on The Holocaust, to 26 governments who signed the Declaration by United Nations.
December 12 – WWII: German troops began Operation Winter Storm, an attempt to relieve encircled Axis forces during the Battle of Stalingrad.
December 15 – WWII: Guadalcanal Campaign – Battle of Mount Austen, the Galloping Horse, and the Sea Horse: the United States and allied forces begin to attack Japanese positions near the Matanikau River.
December 17 – The Allies issue the Joint Declaration by Members of the United Nations (as the answer to Raczyński's Note), the first time they publicly acknowledge the Holocaust.
An avalanche in
Aliquippa, Pennsylvania, kills 26, including Vulcan Crucible Steel heir-apparent Samuel A. Stafford Sr., when two 100 ton boulders fall on a bus filled with wartime steelworkers on their way home. An airplane carrying prominent Ustashe general Jure Francetić crashes. Francetić dies as a result of the injuries on December 27.
December 24 – French Admiral Darlan, the former Vichy leader who has switched over to the Allies following the Torch landings, is assassinated in Algiers.
December 27 – The Union of Pioneers of Yugoslavia is founded.
December 28 – North Atlantic Convoy ON 154 is heavily attacked by U-boats, sinking 13 ships.  December 31 - The Times Square Ball in Times Square, New York City isn't dropped for the first time. Instead, there is a moment of silence at midnight, followed by the sound of bells playing from sound trucks at the base of One Times Square.