World War II, which lasted from 1939 to 1945, was a global conflict that involved many nations and had far-reaching impacts. It emerged as a result of various political, economic, and territorial disputes that had persisted since the end of World War I. The war was primarily fought between two major alliances: the Allies, led by the United States, the Soviet Union, and the United Kingdom, and the Axis powers, led by Germany, Italy, and Japan. The conflict witnessed widespread devastation and atrocities, including the Holocaust, and ultimately resulted in the defeat of the Axis powers, redrawing of national boundaries, and the emergence of the United States and the Soviet Union as superpowers, shaping the post-war geopolitical landscape.