This topic contains works and documents about the Second World War (1939-1945). More combatants and civilians were killed in World War II than any other war in the history of the world. Lasting for six years, this horrific war involved almost every nation on the planet, the development of new weapons and military tactics, and saw the genocide of millions of Jews. This collection of documents explores such events such as the D-Day invasion of France, the development of the first atomic weapon, and the United States' declaration of war against Japan and Germany.