
World War II, or the Second World War (often abbreviated as WWII or WW2), was a global war that was under way by 1939 and ended in 1945. It involved a vast majority of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis. It was the most widespread war in history, with more than 100 million people serving in military units. In a state of "total war", the major participants placed their entire economic, industrial, and scientific capabilities at the service of the war effort, erasing the distinction between civilian and military resources. Marked by significant events involving the mass death of civilians, including the Holocaust and the only use of nuclear weapons in warfare, it resulted in 50 million to over 70 million fatalities. These deaths make the war the deadliest conflict in human history.
Research Aids
- World War II Museum
- How to locate someone who fought in World War II
- Finding a Military Unit
List of Miscellaneous World War II Projects
- Blacks in World War II
- Dunera Boys
- European Resistance Movements
- The Ghetto Swingers
- Home Front During World War II
- Jewish Paratroopers Behind Nazi Lines
- Jewish Partisans
- Jewish Soldiers in World War II
- Jews of St. Martin Vésubie
- The Kindertransport
- Medal of Honour Recipients
- Memorials/Cemeteries
- Notables of World War II
- Resistance Movements During World War II
- The Sound of Music
- Stolpersteine
- Suicide In Response To Nazi Oppression
- Unit Directory
- War Brides
- World War II - Casualties
- World War II - Veterans & Survivors
The Holocaust
- American Victims of the Holocaust
- Anne Frank * Brody is No More
- Children of the Holocaust
- Deaf Holocaust & Survivors
- European Rabbis that Perished in the Holocaust
- Heroes of the Holocaust
- Holocaust in Greece
- Holocaust in Latvia
- Holocaust in the Netherlands
- Holocaust in Romania
- Holocaust in Ukraine
- Holocaust Life Saving Visas Issued by Consul General George Waller, Jr. in Luxembourg (1940-1941)
- Holocaust of Maramaros
- Holocaust Survivors
- Holocaust Survivors - With Displaced Persons & Work Camps
- Holocaust Remembrance Day
- Holocaust Victims From Jerusalem
- Holocaust Victims in Rotterdam
- Holocaust Victims of Norway
- Jewish Murder Victims in a Lime Kiln in the Village of Nemeck (Holocaust 1945)
- Purple Triangle
- Reich Refugees During the Holocaust
- Schindler's List: The Girl in the Red Coat
- Secret Swiss Holocaust Lifesaving El Salvador Citizenship Certificates
- Unknown Saltiel Holocaust Victims
- Sosúa: Caribbean Haven for Jewish Refugees
- Victims of the Nazi Holocaust
World War II Geni Projects by Country
Australia
- Australia in World War II
- Australian Casualties of World War II
- Australian Memorials & Cemeteries of World War II - Sydney
- South Australia Casualties of World War II
Austria
Belarus
Belgium
- German Jews Who Emigrated to Belgium (1934-1940)
- Prisoners Incarcerated by the Nazis in Fort Breendonk
Brazil
Brazilian Expeditionary Force (FEB)
Canada
China
Croatia
- Croatian Soldiers & Victims of World War II
- Split Citizens Killed During the National Liberation War in World War II
Czechoslovakia
Egypt
Estonia
Finland
- The Continuation War (1941-1944)
- Died in the Finnish Wars (1939-1945)
- Finnish & Karelian Victims of Soviet Persecution
- Finnish War Children
- Finns in World War II
France
Germany
- Bergen-Belsen
- Buchenwald
- Dachau
- Einsatzgruppen
- Foreign Volunteers in the Waffen (1940-1945)
- German Resistance Movement (1933-1945)
- German Soldiers Who Perished During World War II
- Judenhäuser in the Third Reich
- Last Jews in Berlin (1945)
- Nazi Concentration Camps
- Nazi Euthanasia Victims - Aktion T4
- Nazi Germany
- Organisation Todt
- Victims of Kristallnacht
Hungary
- Budapest Ghetto
- Hungarian Labor Service Battalions
- The Kasztner Transports
- Swedish Passport Safe House Survivors
Italy
Japan
Latvia
Lithuania
- Kovno Ghetto
- Lithuanian Massacres
- Lithuanian Partisans (1944-1953)
- Lithuanian Victims of the Nazi Regime
- Soviet Deportation Victims (1941, 1945-1952)
- Vilna Ghetto
- Lithuanians Within WWII Resistance
- Lithuanian victims of Nazi regime
- Rainiai Massacre Victims
- Lithuanian Partisans (1944-1953)
Netherlands
- Dwang-Arbeid (1940-1945)
- World War II - Sinking of the SS Slamat (April 1941)
- Vrouwen in Verzet (1940-1945)
New Zealand
- Armed Forces New Zealand - World War II
- Sinking of the SS Chakdina (December 1941)
- War Memorials Index
- World War II Roll of Honour
Norway
Philippines
Poland
- Anders' Army of Poland
- Auschwitz
- Majdanek Extermination Camp
- Poles Deported to Siberian Gulags/Soviet Repressions during World War II
- Polish Resistance Movements during WWII
- Polish Ghettos in World War II
- Ponary Massacre
- Katyn 1940
- Warsaw Ghetto Uprising
- Warsaw Uprising in 1944
Rhodesia
Romania
Russia (Soviet Union)
Slovenia
South Africa
- 2 Squadron SAAF pilots in the Ethiopian campaign 1941
- South African World War II Casualties
- South African World War II Participants
- South African World War II PORTAL
Ukraine
United Kingdom
- World War II - 1939-1945 - Armed Forces England
- World War II - Royal Army Service Corps
- The Sinking of the Nova Scotia (1942)
United States of America
- Americans in World War II
- Camp Algiers - WWII Internment Camp
- Doolittle's Tokyo Raiders
- Fort Ontario, New York European Refugees
- Hickam Field
- Honor Roll of the Dead & Missing - San Mateo County, California
- The Incarceration of Japanese Americans and the War Relocation Authority During World War II
- Naval Air Station Pearl Harbor
- Rosie the Riveter
- Seabees in World War II
- Women's Airforce Service Pilots (WASP) in World War II
- World War II - American Waves
- World War II - Pearl Harbor - USS Arizona
- World War II - Pearl Harbor - USS California
- World War II - Pearl Harbor - USS Nevada
- World War II - Pearl Harbor - USS Oklahoma
- World War II - Pearl Harbor - USS Tennessee
- World War II - Pearl Harbor - USS Utah
- World War II - Pearl Harbor - USS West Virginia
- Tuskegee Airmen
Prisoners of War
- World War II - American Prisoners of War
- World War II - Australian Prisoners of War
- World War II - British Prisoners of War
- World War II - Canadian Prisoners of War
- World War II - Polish Prisoners of War
- South African Prisoners of War
- World War II - Prisoners of War - Stalags
- World War II - Stalag I B Hohenstein
List of World War II Battles
African & Middle Eastern Front
- Battles of Fort Capuzzo (June 1940 - November 1942)
- East African Campaign (June 1940 - November 1942)
- Battle of Dakar (September 1940)
- Battle of Gabon (November 1940)
- Operation Compass (December 1940 - February 1941)
- Battle of Keren ( February 1941 - April 1941)
- Siege of Tobruk (April 1941 - November 1941)
- Operation Torch (November 1942)
Tunisia Campaign
- Battle of Kasserine Pass (November 1942 - May 1943)
- Battle of Sidi Bou Zid (November 1942 - May 1943)
- Battle of Medenine (November 1942 - May 1943)
- Operation Pugilist (November 1942 - May 1943)
- Battle of El Guettar (November 1942 - May 1943)
- Battle of Hill 609 (November 1942 - May 1943)
- Operation Vulcan (November 1942 - May 1943)
Iraq Campaign (22 May 1941)
- Operation Brevity ( May 1941)
- Operation Skorpion (May 1941)
- Operation Battleaxe (June 1941)
Syria-Lebanon Campaign (June 1941 - July 1941)
Iran Campaign (June 1941 - July 1941)
- Battle of Gondar (November 1941)
- Operation Crusader (November 1941 - December 1941)
- Battle of Gazala (May 1942 - June 1942)
- Battle of Madagascar (May 1942 - November 1942)
- First Battle of El Alamein (July 1942)
- Battle of Alam el Halfa (August 1942 - September 1942)
- Second Battle of El Alamein (October 1942 - November 1942)
- Battle of El Aghelia (December 1942)
- Operation Terminal (November 1942)
- Battle of Casablance ( November 1942)
Mediterranean Front
- Attack on Mers-el-Kebir (3 July 1940)
- Siege of Malta (June 1940 - December 1942)
- Battle of Yugoslavia (April 1941)
- Battle of Greece (April 1941)
- Battle of Crete (May 1941)
- Operation Strangle - Sicily (March 1943 - June 1944)
- Operation Ladbroke - Sicily (July 1943 - August 1943)
- Operation Fustian - Sicily (July 1943 - August 1943)
- Battle of Troina (July 1943 - August 1943)
- Operation Slapstick - Italy (September 1943)
- Battle of Leros (September 1943 - October 1943)
- Battle of Kos (September 1943 - October 1943)
- Battle of Naples (September 1943)
- Volturno Line (October 1943 - November 1943)
- Barbara Line (October 1943 - November 1943)
- Air Raid on Bari (December 1943)
- Battle of Ortona (December 1943)
- Bernhardt Line (December 1943 - January 1944)
- Moro River Campaign (December 1943)
- Battle of Monte Cassino (January 1944 - May 1944)
- Operation Diadem (January 1944 - May 1944)
- Battle of Anzio (January 1944 - June 1944)
- Battle of Cisterna (January 1944 - June 1944)
- Trasimene Line (June 1944 - July 1944)
- Battle of Ancona (June 1944 - July 1944)
- Gothic Line (August 1944 - December 1944)
- Battle of Gemmano (August 1944 - December 1944)
- Battle of Rimini (August 1944 - December 1944)
- Battle of San Marino (September 1944)
- Battle of Garfagnana (December 1944)
- Battle of Monte Castello (November 1944 - February 1945)
- Battle of Bologna - Italy (April 1945 - May 1945)
- Battle of Collecchio - Italy (April 1945 - May 1945)
- Battle of the Argenta Gap - Italy (April 1945 - May 1945)
Western Front
- Saar Offensive (September 1939)
- Operation Weserubung (April 1940 - June 1940)
- Battle of Rotterdam - Netherlands (May 1940)
- Battle of Zeeland - Netherlands (May 1940)
- Battle of the Afsluitdijk - Netherlands (May 1940)
- Battle of the Grebbeberg - Netherlands (May 1940)
- Battle of the Hague - Netherlands (May 1940)
- Battle of Maastricht - Netherlands (May 1940)
- Battle of Fort Eben-Emael - Belgium (May 1940)
- Battle of Hannut - Belgium (May 1940)
- Battle of Gembloux - Belgium (May 1940)
- Battle of Sedan - France (May 1940 - June 1940)
- Battle of Arras - France (May 1940 - June 1940)
- Siege of Calais - France (May 1940 - June 1940)
- Siege of Lille - France (May 1940 - June 1940)
- Operation Paula - France (May 1940 - June 1940)
- Battle of Dunkirk - France (May 1940 - June 1940)
- Battle of Saumur - France (May 1940 - June 1940)
- Battle of Britain (July 1940 - October 1940)
- The Blitz (September 1940 - May 1941)
- Operation Cerberus (February 1942)
- Operation Donnerkeil (February 1942)
- St. Nazaire Raid (March 1942)
- Dieppe Raid (August 1942)
- Battle of Berlin - Air (November 1943 - March 1944)
- Operation Neptune
- Operation Overlord - Battle of Normandy (June-July 1944)
- D-Day (June 6, 1944)
- Battle for Caen - Normandy
- Operation Perch - Normandy
- Battle of Carentan - Normandy
- Battle of Cherbourg - Normandy
- Battle of Villers-Bocage - Normandy
- Battle of Bloody Gulch - Normandy
- Operation Epsom - Normandy
- Operation Windsor - Normandy
- Operation Charnwood - Normandy
- Battle of Saint-Lô (July 1944)
- Operation Jupiter - Normandy
- Second Battle of the Odon - Normandy
- Operation Goodwood - Normandy (July 1944)
- Operation Atlantic - Normandy
- Battle of Verrieres Ridge - Normandy
- Operation Spring - Normandy
- Operation Cobra - Normandy (July 1944)
- Operation Totalize - Normandy
- Operation Luttich - Normandy
- Operation Tractable - Normandy
- Battle of Hill 262 - Normandy
- Falaise Pocket - Normandy
- Battle for Brest (August 1944 - September 1944)
- Operation Dragoon (August 1944 - September 1944)
- Operation Romeo (August 1944 - September 1944)
- Battle of Port Cros (August 1944 - September 1944)
- Battle of La Ciotat (August 1944 - September 1944)
- Allied Advance from Paris to the Rhine (August 1944 - September 1944)
- Operation Astonia
- Siege of Dunkirk
- Operation Wellhit
- Operation Undergo
- Operation Market Garden (September 1944)
- Battle of Arnhem (September 1944)
- Lorraine Campaign (September 1944 - December 1944)
- Battle of Metz (September 1944 - December 1944)
- Battle of Nancy (September 1944)
- Battle of Moerbrugge (September 1944)
- Battle of Hürtgen Forest (September 1944 - February 1945)
- Battle of Hill 400 (September 1944 - February 1945)
- Battle of Overloon (October 1944)
- Battle of Aachen (October 1944)
- Battle of Crucifix Hill (October 1944)
- Battle of the Scheldt (October 1944 - November 1944)
- Operation Queen (November 1944 - December 1944)
- Operation Clipper (November 1944 - January 1945)
- Battle of the Bulge (December 1944 - January 1945)
- Battle of Vianden
- Battle of St. Vith
- Battle of Kesternich
- Battle of Foy
- Battle of Lanzerath Ridge
- Losheim Gap
- Battle of Clervaux
- Elsenborn Ridge
- Operation Stosser
- Siege of Bastogne (December 1944)
- Operation Bodenplatte
- Operation Nordwind (January 1945)
- Operation Blackcock (January 1945)
- Colmar Pocket (January 1945 - February 1945)
- Western Allied Invasion of Germany: (February 1945 - May 1945)
- Operation Veritable
- Operation Grenade
- Operation Lumberjack
- Operation Plunder
- Operation Varsity
- Operation Undertone
- Operation Amherst
- Battle of Kassel
- Battle of Heilbronn
- Battle of Remagen (March 1945)
- Battle of Groningen (April 1945)
- Battle of Ruhr Pocket (April 1945)
The Atlantic
- Battle of the River Plate
- Altmark Incident
- Convoy SC 7
- Convoy HX 84
- Convoy HX 106
- Operation Berlin
- Action of 4 April 1941
- Action of 9 May 1941
- Battle of the Denmark Strait
- Battle of the Bismarck
- Operation Drumbeat January-August 1942)
- Battle of Torpedo Alley
- Action of 27 March 1942
- Battle of the St. Lawrence
- Action of 6 June 1942
- Convoy PQ 7
- Naval Battle of Casablanca
- Battle of the Barents Sea
- Battle of the North Cape
- Operation Stonewall
- Operation Teardrop
- Action of 13 May 1944
- Battle of Ushant
- Battle of Pierres Noires
- Action of 9 February 1945
- Battle of Point Judith
Eastern Front
- Battle of Tanner
- Battle of Mokra
- Battle of Mlawa
- Battle of Tuchola Forest
- Battle of Jordanow
- Battle of Borowa Góra (September 2-5, 1939)
- Battle of Wizna
- Battle of Piotrkow Trybunalski
- Battle of Hel
- Battle of Bzura
- Siege or Warsaw
- Battle of Lwow
- Battle of Tomaszow Lubelski
- Battle of Krasnobrod
- Battle of Knock
- Soviet Invasion of Poland (September 1939 - October 1939)
- Battle of Wilno
- Battle of Grodno
- Battle of Szack
- Battle of Wytyczno
- Winter War (November 1939 - March 1940)
- Battle of Suomussalmi
- Battle of Summa
- Battle of Raate Road
- Battle of Kollaa
- Battle of Petsamo
- Operation Barbarosa (June 1941 - December 1941)
- Battle of Bialystok-Minsk (June 1941)
- Operation Arctic Fox (July 1941 - November 1941)
- Operation Bagration (June 1941 - August 1941)
- Bobruysk Offensive (June 1944)
- Battle of the Bay of Viipuri (June 1944 - July 1944)
- Belostock Offensive (July 1944)
- Battle of Berlin (April 1945 - May 1945)
- Battle of Bautzen (April 1945)
- Battle at Borodino Field (October 1941 - January 1942)
- Operation Braunschweig (July 1942 - November 1942)
- Defense of Brest Fortress (June 1941)
- Siege of Breslau (February 1945 - May 1945)
- Battle of Brody (June 1941)
- Battle of Bryansk (October 1941)
- Battle of Roy (November 1941)
- Budapest Offensive (October 1944 - February 1945)
- Siege of Budapest (December 1944 - February 1945)
- Operation Buffel (March 1943)
- Case Blue (June 1942 - November 1942)
- Battle of the Caucasus
- Concert (operation)
- Continuation War
- Courland Pocket
- Battle of the Crimea (1941)
- Battle of the Crimea (1944)
- Battle of Debrecen
- Demyansk Pocket
- Operation Doppelkopf
- Battle of the Dnieper
- Battle of the Transdanubian Hills
- Battle of the Dukla Pass
- East Pomeranian Offensive
- East Prussian Offensive
- Operation Eidelweiss
- Operation Fruhlingserwachen
- Gumbinnen Operation
- Battle of Halbe
- Battle of Hel
- Heiligenbeil Pocket
- Operation Iskra
- Jassy-Kishinev Operation
- Kamanets-Podolsky Pocket
- Kaunas Offensive
- Battle of the Kerch Peninsula
- Kerch-Eltigen Operation
- First Battle of Kharkov (1941)
- Second Battle of Kharkov
- Third Battle of Kharkov
- Fourth Battle of Kharkov
- Occupation of Kharkov
- Battle of Kiev (1941)
- Battle of Kiev (1943)
- Battle of Kolberg
- Battle of Konigsberg (1945)
- Operation Konrad
- Korsun-Cherkassy Pocket
- Battle of Krasny Bor
- Operation Kremlin
- Battle of Kursk
- Operation Kutuzov
- Siege of Leningrad (1941-1944)
- Battle of Lenino
- Lower Silesian Offensive
- Lublin-Brest Offensive
- Lvov-Sandomierz Offensive
- Lotzen Decision
- Operation Margarethe
- Battle of Memel * Minsk Offensive
- Mogilev Offensive
- Moonzund Landing Operation
- Battle of Moscow
- Malaya Zemlya
- Operation Mars
- Nagykanizsa-Kermend Offensive
- Battle of Narva (1944)
- Battle for Narva Bridgehead
- Battle of Tannenberg Line
- Nevsky Pyatachok
- Battle of Nikolayevka
- Operation Nordlicht
- Battle of the Oder-Neisse
- Siege of Odessa (1941)
- Osovets Offensive
- Ostrogozhsk-Rossosh Operation
- Operation Panzerfaust
- Operation Platinum Fox
- Polotsk Offensive
- Operation Polyarnaya Zvezda
- Battle of Porkuni
- Battle of Poznan (1945)
- Prague Offensive
- Pripyat Swamps (punitive operation)
- Battle of Prokhorovka
- Battle of Radzymin (1944)
- Battle of Raseiniai
- Operation Renntier
- Riga Offensive (1944)
- Battle of Rostov
- Battles of Rzhev
- Operation Saturn
- Defense of Schwedt Bridgehead
- Sea of Azov coastal advance
- Battle of the Seelow Heights
- Siege of Sevastopol (1941 - 1942)
- Shyaulyay Offensive
- Silesian Offensives
- Operation Silver Fox
- Battle of Smolensk (1941)
- Battle of Smolensk (1943)
- Operation Solstice
- Battle of Someri
- Battle of Stalingrad
- Battle of Studzianki
- Bombing of Tallinn
- Evacuation of Tallinn (1941)
- Tallinn Offensive
- Battle of Targul Frumos
- Tatsinskaya Raid
- Toropets-Kholm Operation
- Battle of Uman
- Upper Silesian Offensive
- Operation Uranus
- Battle for Velikiye Luki (1943)
- Vienna Offensive
- Vilnius Offensive
- Vistula-Oder Offensive
- Vitebsk-Orsha Offensive
- Battle of Voronezh (1942)
- Battle of Voronezh (1943)
- Warsaw Uprising
- Battle of Westerplatte
- Operation Wintergewitter
- Battle of Wizna
- Operation Wotan
- Yelnya Offensive
- Zemland Offensive
- Operation Valkyrie
The Pacific
- New Guinea Campaign
- Battle for Kokoda
- Battle of Biak
- Battle of Buna-Gona
- Battle of the Bismarck Sea
- Battle of Driniumor River
- Finisterre Range Campaign
- Huon Peninsula Campaign
- Battle of Lone Tree Hill (1944)
- Battle of Milne Bay
- Operation Mo
- Operations Reckless and Persecution
- Salamauna-Lae Campaign
- Battle of Wau
- Bombing of Wewak
- Attack on Broome
- Battle of Darwin
- Attack on Pearl Harbor (7 December 1941)
- Battle of Corregidor
- Battle of Hong Kong (December 1941)
- Dutch East Indies Campaign (December 1941 - March 1942)
- Battle of Guam (December 1941)
- Battle of Wake Island (December 1941)
- Battle of Rabaul (January-February 1942)
- Battle of Bataan (January-April 1942
- Bataan Death March (April 1942)
- Battle of the Coral Sea (May 1942)
- Battle of Midway (June 1942)
- Aleutian Islands Campaign (June 1942-August 1943)
- Guadalcanal Campaign (August 1942 - February 1943)
- Battle of the Eastern Solomons (August 1942)
- Battle of Tulagi & Gavatu Tanambogo (August 1942)
- Battle of Savo Island (August 1942)
- Battle of the Santa Cruz Islands (October 1942)
- Battle of Esperance or Second Battle of Savo Island (October 1942)
- Operation Cartwheel (1943-1944)
- Battle of Attu (May 1943)
- Battle of Vella Lavella (August-November 1943)
- Battle of Tarawa (November 1943)
- Battle of Cape Gloucester (December 1943 - April 1944)
- Battle of Kwajalein (January 1944 - February 1944)
- Battle of Eniwetok (February 1944)
- Battle of Saipan (June 1944 - July 1944)
- Battle of Noemfoor (July 1944 - August 1944)
- Battle of Guam (July 1944 - August 1944)
- Battle of Tinian (July 1944 - August 1944)
- Battle of Peleliu (15 September 1944 - 17 November 1944)
- Battle of the Philippine Sea (September 1944 - October 1944)
- Battle of Morotai (September 1944 - October 1944)
- Battle of Leyte Gulf (October 1944)
- Philippines Campaign (October 1944 - September 1945)
- Battle of Leyte (October-December 1944)
- Battle of Bataan (January-February 1945)
- Battle of Luzon (January-August 1945)
- Battle of Iwo Jima (February 1945 - March 1945)
- Battle of Visayas (March-August 1945)
- Battle of Manila (February-March 1945)
- Battle of Okinawa (April 1945 - June 1945)
- Atomic Bombings of Hiroshima & Nagasaki (August 1945) (Bombing of Japan)