During World War II, the Germans first bombed London (1940-41), in what came to the known as the London Blitz, short for blitzkrieg in German. By this time in 1944, the weapon of choice was the Fieseler Fi 103, better known as V-1 (German: Vergeltungswaffe. The V-1 was actually an early cruise missile used during the war. The V-1 was developed at Peenemünde by the German Luftwaffe. Between June 1944 and 29 March 1945, it was fired at population centers such as London and Antwerp. V-1s were launched from "ski" launch sites along the French (Pas-de-Calais) and Dutch coasts.
It would get much worse. In September, 1944, the Germans launched the first V-2 attacks against London and other points, eventually killing an estimated 9,000 civilians and military personnel as well as causing untold property damage.