- King of England 1087–1100 (son of William I, duke of Normandy).
- king of Prussia and emperor of Germany 1888–1918.
- known as William Rufus. ?1056–1100, king of England (1087–1100); the son of William the Conqueror. He was killed by an arrow while hunting in the New Forest
- known as William the Good . 1154–89, last Norman king of Sicily (1166–89)
- 1792–1849, king of the Netherlands (1840–49); son of William I
- German name Kaiser Wilhelm. 1859–1941, German emperor and king of Prussia (1888–1918): asserted Germany's claim to world leadership; forced to abdicate at the end of World War I
