WORLD WAR II

WWII or WW2, was a global war that lasted from 1939 to 1945.

 It involved the vast majority of the world's countries—including all the great powers—forming two opposing military alliances: the Allies and the Axis. In a state of total war, directly involving more than 100 million personnel from more than 30 countries, the major participants threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. World War II was the deadliest conflict in human history, resulting in 70 to 85 million fatalities, with more civilians than military personnel killed. Tens of millions of people died due to genocides (including the Holocaust), premeditated death from starvation, massacres, and disease. Aircraft played a major role in the conflict, including in strategic bombing of population centres, the development of nuclear weapons, and the only two uses of such in war.

World War II is generally considered to have begun on 1 September 1939, with the invasion of Poland by Germany and subsequent declarations of war on Germany by the United Kingdom and France on the 3rd. From late 1939 to early 1941, in a series of campaigns and treaties, Germany conquered or controlled much of continental Europe, and formed the Axis alliance with Italy and Japan, along with other countries later on. Under the Molotov–Ribbentrop Pact of August 1939, Germany and the Soviet Union partitioned and annexed territories of their European neighbours: Poland, Finland, Romania and the Baltic states. Following the onset of campaigns in North Africa and East Africa, and the fall of France in mid-1940, the war continued primarily between the European Axis powers and the British Empire, with war in the Balkans, the aerial Battle of Britain, the Blitz, and the Battle of the Atlantic. On 22 June 1941, Germany led the European Axis powers in an invasion of the Soviet Union, opening the Eastern Front, the largest land theatre of war in history and trapping the Axis, crucially the German Wehrmacht, in a war of attrition.

World War II changed the political alignment and social structure of the globe. The United Nations (UN) was established to foster international co-operation and prevent future conflicts, and the victorious great powers—China, France, the Soviet Union, the United Kingdom, and the United States—became the permanent members of its Security Council. The Soviet Union and the United States emerged as rival superpowers, setting the stage for the nearly half-century-long Cold War. In the wake of European devastation, the influence of its great powers waned, triggering the decolonisation of Africa and Asia. Most countries whose industries had been damaged moved towards economic recovery and expansion. Political integration, especially in Europe, began as an effort to forestall future hostilities, end pre-war enmities and forge a sense of common identity.