# Dictionary of National Biography, 1885-1900/Mortain, Robert of

​MORTAIN, ROBERT of, Count of Mortain, in the diocese of Avranches (d. 1091?), was uterine brother of William the Conqueror. He was the second son of Herlwin of Conteville, by his wife Herleva. His elder brother was Odo [q. v.], bishop of Bayeux. William the Warling, a cousin of Duke William, was in 1048-9 deprived of the county of Mortain, which was handed over to Robert, an instance of William's desire 'to raise up the humble kindred of his mother' while 'he plucked down the proud kindred of his father' (Will. of Jumièges, vii. 19). In 1066 Robert was present at the select council held at Lillebonne to discuss the invasion of England; he contributed 120 ships to the fleet, according to Wace, a fact of doubtful authenticity (Stubbs, Const. Hist. i. 279 note), and fought at Senlac (Roman de Rou, 1.13765). In 1069 he was left in England to protect Lindsey against the Danes, and at the same time his castle of Montacute (Eng. Lutgaresburg) in Somerset was besieged. When William I lay dying, Robert was present and pleaded the cause of his brother Odo with success. He joined with Odo in supporting Robert Curthose against William II, and held the castle of Pevensey against the king from April to June 1088 (Ordericus Vitalis, iv. 17), but he soon yielded and was reconciled to Rufus.
His possessions in England were larger than those of any other follower of William (Freeman, Norman Conquest, iv. 764), and have been estimated at 793 manors (Brady, Introd. to Domesday Book, p. 13). Of these, 623 in the south-west counties returned him 400l. a year (Morgan, England under the Normans, p. 8). He had 248 manors in Cornwall, 196 in Yorkshire, 99 in Northamptonshire, 75 in Devonshire, with a church and house in Exeter, 54 in Sussex and the borough of Pevensey, 49 in Dorset, 29 in Buckinghamshire, and one or more in ten other counties (Ellis, i. 455). He was charged by the Domesday jurors with many 'usurpations,' particularly on the see of Exeter, the churches of Bodmin and St. German, Mount St. Michael, Cornwall, and Westminster. The charter which records his grant of Mount St. Michael as a cell to Mont St. Michel is spurious (Freeman, iv. 766). There is no ground for believing that he was Earl of Cornwall (Third Report on the Dignity of a Peer).
He married Matilda, daughter of Roger of Montgomery [q. v.] In 1082 they founded a collegiate church in their castle of Mortain, under the guidance of their chaplain Vitalis, abbot of Savigny. Robert also made grants to Fleury and Marmoutier (Stapleton, Rot. Scacc. Nor. i. p. lxxv), and gave to Fecamp what he took from Westminster Domesday Book, f. 129). He had a son William, who forfeited Mortain after the battle of Tinchebrai, and possibly a son Nigel (Stapleton, i. p. lxvii). His daughter Agnes married Andrew of Vitré, another married Guy de la Val, and another the Earl of Toulouse.
Robert died in 1091 (Kelham, Domesday Book Illustrated, p. 39, quoting Heylin and Mills, Catalogue of Honor).
[Ordericus Vitalis, ed. Le Prevost, ii. 194-223, 12, iii. c. xi. and p. 449, iv. 17; Domesday Book; Freeman's Norman Conquest, vols. ii-v. passim, and William Rufus.]
M. B.