Robert de Mowbray

Robert de Mowbray (died 1125), a Norman, was Earl of Northumbria from 1086, until 1095, when he was deposed for rebelling against William Rufus, King of England. He was the son of Roger de Mowbray and nephew of Geoffrey de Montbray, bishop of Coutances. The family name derives from Montbrai in Manche, Normandy, Mowbray being an Anglicisation of it.

Robert was made Earl of Northumbria after Aubrey de Coucy, the previous earl decided that he no longer wished to remain in his post. Coucy was made earl in 1080 and, probably that same year, resigned his position and returned to Normandy losing all of the lands that he held in England. He was not replaced until Robert was appointed in 1086.

In 1088 Robert and his uncle, Geoffrey, sided with Robert, duke of Normandy, in the rebellion against William Rufus, and both were active militarily. The rebellion failed but the king subsequently pardoned them both, and Robert remained in his post as Earl of Northumbria.

In November 1093 Malcolm III of Scotland invaded Northumbria for the second time since 1091, and attacked Alnwick. Robert de Mowbray raised an army and attacked the Scots taking them by surprise on 13 November (St Brice’s Day). In the ensuing conflict, known as the Battle of Alnwick, Malcolm and his son Edward were slain. Earlier that same year Geoffrey de Montbray died and Mowbray succeeded to his uncle's large estates, so becoming one of the most powerful barons in the kingdom.

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