Major events of World War II include Germany's invasion of Austria, the Treaty of Munich, the subsequent German invasion of Czechoslovakia and Poland, formal declarations of war by Britain and France, the entrance of Japan into the war, the suicide of Adolf Hitler and the dropping of atomic bombs on Hiroshima and Nagasaki. The war formally began in September of 1939 and ended in September of 1945.
Major events leading up to the formal declaration of war by France and Britain are Germany's annexation of Poland in 1938, the Treaty of Munich that same year, and the invasion of Czechoslovakia the following year, which was in violation of the treaty. The invasion of Poland in September of 1939 led France and Britain to finally declare war on Germany.
Germany occupied Denmark and Norway and began their "blitzkrieg" attack on Belgium and Holland in May of 1940. Italy entered the war on Germany's side in June of 1940. Germany also occupied France under armistice in this month, and the Battle of Britain began the following month. Germany invaded Russia in June of 1941 and the Japanese attacked Pearl Harbor in December of 1941, drawing Russia and the United States into the war.
In June of 1942, the US defeated Japan in the Battle of the Midway. The Russians won their first battle against Germany in November of 1942 at Stalingrad. In 1943, the Allied forces retook North Africa and invaded Italy, leading to Italy's surrender. The Allied attack on Normandy, better known as "D-Day," occurred in June of 1944. Paris was liberated in August of 1944.
Hitler committed suicide in April of 1945, leading to German surrender in May of 1945. U.S. forces dropped atomic bombs in Hiroshima and Nagasaki in August of that year, leading to Japan's surrender and the end of the war.