Japan formally signed the surrender documents on board the USS Missouri, officially ending World War II.

Japan announced its unconditional surrender, and Emperor Hirohito communicated this decision to the Japanese people.

The United States dropped an atomic bomb on Nagasaki, following the earlier bombing of Hiroshima, leading to Japan's decision to surrender.

Germany signed an unconditional surrender, marking the end of World War II in Europe.

Hitler committed suicide in his headquarters, and German forces in Italy surrendered.

Germany launched a last major counter-offensive in the Ardennes, known as the Battle of the Bulge, in an attempt to split the Allies.

The Soviet Red Army, with limited support from Bulgarian forces, assisted the Partisans in a joint liberation of the capital city of Belgrade.

Paris was liberated by the local resistance and the Free French Forces, assisted by the Western Allies.

The Western Allies invaded northern France on D-Day, marking a significant turning point in the war.

Rome was captured by the Allies, marking a significant advance in Italy.

Soviet troops launched a major offensive that expelled German forces from the Leningrad region, ending the most lethal siege in history.

Japan attacked British and American holdings with near-simultaneous offensives against Southeast Asia and the Central Pacific, including the attack on Pearl Harbor.

Germany, supported by Italy and Romania, invaded the Soviet Union in Operation Barbarossa, aiming to eliminate the Soviet Union as a military power and secure strategic resources.

Paris fell to German forces, and France was divided into German and Italian occupation zones and an unoccupied rump state under the Vichy Regime.

Germany launched an offensive against France, and Winston Churchill replaced Neville Chamberlain as the Prime Minister of the United Kingdom.

The last large operational unit of the Polish Army surrendered, although Poland never formally surrendered and continued to resist through a government-in-exile and clandestine state apparatus.

The Warsaw garrison surrendered to the Germans, marking a significant defeat for Poland.

The Soviet Union invaded Poland under the pretext that the Polish state had ceased to exist, following the Molotov–Ribbentrop Pact.

The United Kingdom and France declared war on Germany in response to Germany's invasion of Poland.

Germany, under Adolf Hitler, invaded Poland, leading the United Kingdom and France to declare war on Germany. This event is generally considered the start of World War II.

The Second Sino-Japanese War began with Japan capturing the former Chinese imperial capital of Peking after the Marco Polo Bridge incident. This marked a significant escalation of the conflict between Japan and China.

Italy invaded the Ethiopian Empire (Abyssinia), leading to the military occupation of Ethiopia and its annexation into the newly created colony of Italian East Africa. This exposed the weakness of the League of Nations in preserving peace.

Japan staged the Mukden incident as a pretext to invade Manchuria and establish the puppet state of Manchukuo. This event marked the beginning of Japan's aggressive expansion in China.