In September 1939, Hitler's Nazi Germany invaded Poland. Thus began the greatest armed struggle in history. Within days of the invasion, Germany was at war with France, Great Britain and much of the Commonwealth, but by the end of 1941 – by which time Japan and the United States had been plunged into war – the conflict had engulfed virtually the entire planet. World War II witnessed the mobilisation of more than 100 million military personnel. Here was 'total war' on a scale never previously experienced by any of the countries involved. The conflict eclipsed everything: industry, technology, the economy and home life. It transformed the lives of an entire generation of men and women, who grew up under the shadow of violence, separation and loss. It was also fought in every conceivable terrain and theatre, from the arctic conditions of the Soviet winter to the tropical landscape of the Pacific islands, with the battle for seas and skies being equally brutal. By the time it ended in September 1945, World War II had claimed the lives of more than 50 million people, and it witnessed the only use of nuclear weapons in warfare to this day. The World War II Story charts the dramatic narrative of the conflict from its first shots to its final apocalyptic end.