World War II lasted from 1939 to 1945, which is more than seven years. This war resulted in close to 50 million deaths, making it the bloodiest conflict in world history. The two main groups fighting were the Axis powers... More »

World War I lasted four years, three months and two weeks, beginning in July 1914 and ending in November 1918. The conflict started with Austria-Hungary declaring war on Serbia in retaliation for the assassination of Arc... More »

www.reference.com History Modern History World War 1

World War II lasted approximately six years. The war began with the Nazi invasion of Poland on Sept. 1, 1939, and ended with Japan's surrender in August 1945. More »

www.reference.com History Modern History World War 2

Historians do not have a general consensus on the exact starting point of World War II. The first formal declarations of war among the major powers involved were in 1937, when Japan and China went to war, and in 1939, wh... More »

www.reference.com History Modern History World War 2

World War II lasted approximately six years. The war began with the Nazi invasion of Poland on Sept. 1, 1939, and ended with Japan's surrender in August 1945. More »

www.reference.com History Modern History World War 2

World War II lasted six years in Europe and eight years in the Pacific. American involvement in the war lasted four years from December 1941, when Japan attacked Pearl Harbor, to 1945, when both Japan and Germany were de... More »

There were two leaders of Japan during World War II: Hirohito and Hideki Tojo. Hirohito was emperor of Japan, while Hideki Tojo was Prime Minister, a general of the Imperial Japanese Army and the leader of the Imperial R... More »