William I

American  

noun

1. the Conqueror, 1027–87, duke of Normandy 1035–87; king of England 1066–87 (son of Robert I, duke of Normandy).

2. Also 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.

3. Also Wilhelm I. Wilhelm Friedrich Ludwig, 1797–1888, King of Prussia 1861–88; emperor of Germany 1871–88 (brother of Frederick William IV).

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William I British  

noun

1. 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

2. known as William the Bad . 1120–66, Norman king of Sicily (1154–66)

3. 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

4. 1772–1843, king of the Netherlands (1815–40): abdicated in favour of his son William II

5. German name Wilhelm I. 1797–1888, king of Prussia (1861–88) and first emperor of Germany (1871–88)

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Example Sentences

See Examples For:

William I

As the sensitive, flute-playing heir of the boorish, beer-swilling Frederick William I, the young prince had scant interest in soldiering.

From The Wall Street Journal ● Apr. 27, 2026

Built by King William I after his conquest of England in 1066, it served as a royal residence for several hundred years, but is more famous as a prison.

From Seattle Times ● Feb. 29, 2024

However, the pace of unification stalled when the new king, William I of Prussia, sought to double the size of his army, and middle- class liberals opposed compulsory military service.

From Textbooks ● Dec. 14, 2022

Conversely, on discovering her late husband’s illness and at his death, “it was William I called first.”

From Washington Post ● Oct. 19, 2021

William I: First constitutional King of Holland, oldest son of William V, has learned a good deal abroad, but only during the last ten years of his exile.

From The Rise of the Dutch Kingdom 1795-1813 by Van Loon, Hendrik Willem