Robert, 1st Earl of Gloucester

Illegitimate son of Henry I of England (c.1090–1147)

Robert FitzRoy, 1st Earl of Gloucester (c. 1090 – 31 October 1147), was an illegitimate son of King Henry I. He was the half-brother of the Empress Matilda, and her chief military supporter during the civil war known as the Anarchy, in which she vied with Stephen of Blois for the throne of England.

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