Robert de Mortain

Robert, Count of Mortain, 2nd Earl of Cornwall (c. 1031–1090) was a Norman nobleman and the uterine half-brother of King William the Conqueror. He was one of the very few proven companions of William the Conqueror at the Battle of Hastings and as recorded in the Domesday Book of 1086 was one of the greatest landholders in his half-brother's new Kingdom of England.

Robert was the son of Herluin de Conteville and Herleva of Falaise and brother of Odo of Bayeux. Robert was born c. 1031 in Normandy, a half-brother of William the Conqueror. and was probably not more than a year or so younger than his brother Odo, born c. 1030. About 1035, Herluin, as Vicomte of Conteville, along with his wife Herleva and Robert, founded Grestain Abbey.

In c. 1049 his brother Duke William made him Count of Mortain, in place of William Werlenc, who had been banished by Duke William; according to Orderic Vitalis, on a single word. William Werlenc was a grandson of Duke Richard I and therefore a cousin once removed to William, Duke of Normandy. Securing the southern border of Normandy was critical to Duke William and Robert was entrusted with this key county which guarded the borders of Brittany and Bellême.

In early 1066, Robert was present at both the first council of Lillebonne, that of William's inner circle, and the second larger council held to discuss the Duke's planned conquest of England. Robert agreed to provide 120 ships to the invasion fleet, which was more than any other of William's magnates. Robert was one of those few known to have been at the Battle of Hastings in 1066. He is pictured at a dinner at Pevensey on the Bayeux Tapestry, seated with his brothers William and Odo on the day of the landing in England. When granting the monastery of St Michael's Mount to the Norman monastery on the Mont Saint-Michel Robert recorded that he had fought at the Battle of Hastings under the banner of St Michel (habens in bello Sancti Michaelis vexillum).

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