World War II or Second World War was a global conflict that was fought between the Axis powers (led by Nazi Germany, Fascist Italy, and Imperial Japan) against the Allied powers (led by the United Kingdom, USSR and the United States of America). In our history, the war ended with an Allied victory. The war was officially declared in 1939 and ended in 1945. However, the fighting began as early as the mid-1930's with the Italian invasion of Ethiopia and Albania, the Spanish Civil War, the Japanese invasion of China and their attacks on the Soviet Union.
Classic Timeline/RPG Timeline
In the original timeline including Wolfenstein 3D, and Spear of Destiny and any mission packs the war ends in 1945 and mirrors the historical war. The only exception is that Blazkowicz kills Adolf Hitler rather than Hitler committing suicide and ending the war in Europe as a result.
This timeline or timelines is less serious than the war as portrayed in The New Order.
In the MachineGames universe introduced with The New Order, it is revealed that the Allies were winning the war despite the success of Operation Fall Blau and the D-Day landings failure, until 1946 when the Allies began to lose the war due to high tech weapons and by 1948 the Axis powers were near victory. The Nazis had beaten the Allies in creating the first atomic bomb and had it detonated on New York City, having previously defeated Great Britain and the Soviet Union. The United States of America surrendered to the Nazis, ending the war.
The Nazis rule all of Europe and most of the Americas and Asia as a technological advanced totalitarian dictatorship for over 14 years into a retro-futuristic 1960s. Fascist Italy is invaded by Nazi Germany as seen in pieces of newspapers in TNO. Japan was allowed to continue existing as an independent state. As of 1960, the Nazis have conquered 75% of the world and are slowly, but surely, in the process of conquering all of Africa.
By 1961, the Nazis' fortunes had taken a turn for the worse as the intervention of William Blazkowicz and the resurgence of the Kreisau Circle has led to the sabotage of the Nazis' superior technological advantage, culminating in the death of General Deathshead who had led this aggressive advance in science and technology. The Nazis remained in firm control of Europe but the resistance steadily grew in strength and numbers as the Kreisau Circle targeted several Nazi strongholds in Europe before refocusing their efforts on the occupied United States. The destruction of the Nazi leadership triggered a second American Revolution that saw the liberation of the US, threatening the Nazis' vast dominion once more.
By 1980, it is known that the Nazis still controlled France, and presumably many other nations remain in their grip despite America's renewed war effort.
The crimes against humanity are not over as the Nazi's activated a Doomsday device to plunge the whole world into an Apocalypse, a last-ditch attempt to take the whole world down with them, if the allies win World War 3.
World War II on Wikipedia