World War II started on 1st September in the year 1939. The war ended on 2nd September in the year 1945. The invading of Poland by Germany is considered as the start of World War II. During this war there were heavy casualties.A total of 50 million service personnel and civilians is the approximation that has been reached as the casualties of world War II. This was the war that gave rise to two World super powers and they were Russia and United States of America.
