World War II

World War II (WWII or WW2), also called the Second World War and, in the Soviet Union, the Great Patriotic War, was a global war involving fighting in many parts of the world and many countries. Most countries fought 1939–1945 but some started fighting in 1937. Most of the world's countries, including all the great powers, fought as part of two military alliances: the Allies and the Axis Powers. World War II was the deadliest conflict in all of human history. It involved more countries, cost more money, and killed more people than any other war in human history. Between 50 to 85 million people died. The majority were civilians. It included massacres, the deliberate genocide of the Holocaust, strategic bombing, starvation, disease and the first use of nuclear weapons in history.