Timeline of World War II

The deadliest conflict in human history lasted almost exactly six years, beginning with Germany’s invasion of Poland and concluding on the deck of the USS Missouri in Tokyo Bay. Between 40 million and 50 million people died as a result of World War II, and the balance of global power shifted decisively toward the United States and the Soviet Union.

1939

• September 1: Germany invades Poland. Two days later Britain, France, Australia, and New Zealand declare war on Germany.
• September 17: The Soviet Union, acting in accordance with the secret protocols of the Molotov-Ribbentrop Pact, invades eastern Poland.
• October 1939–March 1940: The “Phony War” takes place. The name was coined by journalists to derisively describe the six-month period during which no land operations were undertaken by the Allies or the Germans after the German conquest of Poland.
• November 30: The Soviet Union invades Finland.

1940

• May 14: The government of the Netherlands surrenders. The country’s Queen Wilhelmina escapes to London.
• May 28: King Leopold III surrenders Belgium’s army of 500,000.
• May 26–June 4: Some 198,000 troops of the British Expeditionary Force and 140,000 French and Belgian troops are evacuated from Dunkirk, France.
• June 22: The Battle of France concludes as France signs an armistice agreement with Germany.
• July–September: The Royal Air Force is victorious over the Luftwaffe in the Battle of Britain.
• August 3–6: Over the course of days—and with Germany’s blessing under the Molotov-Ribbentrop Pact—Joseph Stalin forcibly annexes the Baltic states of Lithuania, Latvia, and Estonia.
• September 7, 1940–May 11, 1941: For eight months the Luftwaffe strikes cities in much of the United Kingdom in an effort to bomb the populace into submission. Some 43,000 civilians are killed during the Blitz, but the British remain defiant, embodying the motto “Keep calm and carry on.”
• October 27: Charles de Gaulle establishes the Empire Defense Council to function as the Free French government-in-exile.

1941

• March 11: U.S. Pres. Franklin D. Roosevelt signs the Lend-Lease Act.
• May 27: British warships and air units sink the German battleship Bismarck.
• June 22: Adolf Hitler turns on his former ally when Germany invades the Soviet Union.
• December 7: Japanese air and naval units attack Pearl Harbor and Midway. That same day (December 8 in East Asia) the Japanese strike at Wake Island, Guam, the Philippines, British Malaya, and Hong Kong, and they invade Thailand. The following day Canada, the Dutch government-in-exile, the United States, and Britain will declare war on Japan.

1942

• January 20: Meeting at a villa in the Berlin suburb of Wannsee, Nazi officials plan the “final solution” to the so-called “Jewish question.” Their goal is nothing less than the total extermination of Europe’s Jewish population.
• April 9: The Bataan Peninsula falls to the Japanese after a siege of more than 90 days. Some 76,000 Filipino and American prisoners of war will be forced to undergo a “death march” into captivity. Perhaps 3,000 prisoners will die on the march itself, and tens of thousands more will perish in Japanese captivity.
• April 18: Lieut. Col. James H. Doolittle leads 16 B-25 bombers from the U.S. Navy aircraft carrier Hornet in an audacious surprise attack on the Japanese home islands that causes little damage but boosts Allied morale.
• May 4–8: The U.S. wins a strategic victory at the Battle of the Coral Sea when American carrier aircraft turn back a Japanese invasion force that had been heading for Port Moresby in New Guinea.
• June 3–6: The tide of the war in the Pacific turns when the United States destroys Japan’s first-line carrier strength and most of its best-trained naval pilots at the Battle of Midway.
• July 1: The British Eighth Army checks the advance of German Field Marshal Erwin Rommel’s Afrika Korps into Egypt at El Alamein.
• August 7: United States Marines land on Guadalcanal and Tulagi.
• November 8: Operation Torch begins with the landing of 107,000 U.S. and British troops in an invasion of French North Africa.
• December 9: In the Kokoda Track Campaign on New Guinea, the Australians take Gona from the Japanese. American and Australian forces will capture Buna five days later.

1943

• February 2: The Battle of Stalingrad ends in a Soviet victory with the surrender of the remnants of the German Fourth and Sixth armies. The Axis and Soviet armies engaged at Stalingrad suffered some 2,000,000 casualties, and the battle is regarded by many historians as the most significant engagement of World War II.
• May 13: Less than a week after the fall of Tunis, Axis forces in Tunisia surrender. More than 250,000 prisoners are taken, and North Africa will subsequently serve as a base for future Allied operations against Italy.
• July 5–August 23: The largest tank battle in history occurs at Kursk, Russia, involving some 6,000 tanks, 2,000,000 troops, and 4,000 aircraft. Its conclusion marks the decisive end of German offensive capability on the Eastern Front and clears the way for the great Soviet offensives of 1944–45.
• July 9–10: Allied armies invade Sicily. The conquest of the island will take a little more than a month and lead directly to the fall of Italian dictator Benito Mussolini on July 25.
• September 3: The Allies invade southern mainland Italy, and the Italians surrender almost immediately. German forces in Italy resist the Allied advance, however, and more than a year and a half of heavy fighting will ensue between the initial amphibious landings and the final surrender of German forces in Italy in May 1945.
• November 28: Roosevelt, Churchill, and Stalin open the Tehrān Conference, during which they will agree on final plans to defeat Germany.

1944

• June 4: American Fifth Army enters Rome.
• June 6: The Allies breach Hitler’s Fortress Europe when 160,000 troops invade Normandy in a massive amphibious and airborne assault.
• July 20: Hitler is lightly injured by a bomb in a failed assassination attempt.
• July 23: Soviet forces enter the Majdanek concentration and extermination camp outside Lublin, Poland. It is the first site in the massive Nazi killing apparatus to fall to the Allies.
• August 24: French troops enter Paris.
• October 23–26: At the Battle of Leyte Gulf, American forces effectively destroy the offensive capability of the Japanese Combined Fleet, permitting the U.S. invasion of the Philippines to proceed and expanding Allied control of the Pacific.
• December 16: German forces launch their last major counteroffensive, through the Ardennes Forest, marking the beginning of the Battle of the Bulge.

1945

• January 27: The Red Army liberates the fewer than 8,000 sick or starving prisoners who remain at the Nazi concentration and extermination camp complex called Auschwitz (the German name for Oświęcim, Poland). Between 1940 and 1945, 1.1−1.5 million people died there.
• February 19: United States Marines land on the Japanese island of Iwo Jima (now Iō-tō). Four days later Associated Press photographer Joe Rosenthal will capture one of the most iconic images of the war when a group of Marines raise the American flag over Mount Suribachi.
• April 1: United States Army troops and Marines land on the Japanese island of Okinawa. The battle there will prove to be one of the bloodiest of the Pacific War, a fact that will influence the decision to use the atomic bomb against Japan.
• April 12: Roosevelt dies and Harry S. Truman becomes president of the United States.
• April 21: Soviet forces enter Berlin. The subsequent fighting will be some of the fiercest in the European theater. Red Army casualties will exceed 350,000, and German military casualties will top 450,000. An estimated 300,000 civilians will be killed or wounded.
• April 28: Italian partisans execute Mussolini.
• April 30: As Red Army forces close in, Hitler commits suicide in his bunker in Berlin; two days later German Adm. Karl Dönitz will proclaim himself president of the Reich.
• May 8: The Allies celebrate Victory in Europe (VE) Day following Germany’s unconditional surrender.
• July 16: Manhattan Project scientists detonate Gadget, an experimental atomic bomb, in the New Mexico desert.
• August 6: The United States Army Air Forces B-29 Enola Gay drops an atomic bomb on Hiroshima, Japan. Some 70,000 people are killed instantly, and two-thirds of the city is destroyed.
• August 8: The Soviet Union declares war on Japan.
• August 9: With clouds obscuring its primary target, Kokura (now part of Kitakyūshū), Japan, the B-29 Bockscar proceeds to Nagasaki. The plutonium-fueled bomb dropped on the city kills 40,000 people instantly, and tens of thousands more will succumb to radiation poisoning.
• August 14–15: The Allies celebrate Victory over Japan (VJ) Day after Japan accepts Allied surrender terms. World War II will officially end two weeks later, on September 2, upon Japan’s formal surrender aboard the USS Missouri in Tokyo Bay.