William I

William I noun

the Conqueror, 1027–87, duke of Normandy 1035–87; king of England 1066–87 (son of Robert I, duke of Normandy).
Also Willem I. William I of Orangethe Silent, 1533–84, Dutch leader, statesman, and revolutionary leader born in Germany: prince of Orange 1544–84; count of Nassau 1559–84; 1st stadholder of the United Provinces of the Netherlands 1578–84.
Also Wilhelm I. Wilhelm Friedrich Ludwig, 1797–1888, King of Prussia 1861–88; emperor of Germany 1871–88 (brother of Frederick William IV).

British Dictionary definitions for william i William I noun

known as William the Conqueror. ?1027–1087, duke of Normandy (1035–87) and king of England (1066–87). He claimed to have been promised the English crown by Edward the Confessor, after whose death he disputed the succession of Harold II, invading England in 1066 and defeating Harold at Hastings. The conquest of England resulted in the introduction to England of many Norman customs, esp feudalism. In 1085 he ordered the Domesday Book to be compiled
known as William the Bad . 1120–66, Norman king of Sicily (1154–66)
known as William the Silent. 1533–84, prince of Orange and count of Nassau: led the revolt of the Netherlands against Spain (1568–76) and became first stadholder of the United Provinces of the Netherlands (1579–84); assassinated
1772–1843, king of the Netherlands (1815–40): abdicated in favour of his son William II
German name Wilhelm I. 1797–1888, king of Prussia (1861–88) and first emperor of Germany (1871–88)