As a crucial part of the blitzkrieg that swept across Western Europe in the spring of 1940, German paratroopers made combat drops in Denmark and Norway and then won a brilliant victory in their assault on the Belgian fortress of Eben-Emael. Their most famous airborne operation came in Crete in 1941 when they captured the island but with such high casualties that Hitler would not allow another major drop. Also organized as motorized infantry for ground attacks, the paratroopers saw action at Monte Cassino in Italy, in Normandy, and on the Eastern Front.