From
TCP1:
Robert (De Montgomery, otherwise De Belesme), EARL OF SHROPSHIRE, or SHREWSBURY, and EARL OF ARUNDEL, or SUSSEX, SEIGNEUR DE BELESME, D'ALENCON, &c, in Normandy, b. about 1055; Knighted 1073 ; suc. his parents in their Norman possessions and was generally known by his mother's name of De Belesme. He appears, for a sum of £3,000, to have been confirmed in his brother's Earldoms by William II. in 1098. He, however, fortified his castles in England against Henry I. by whom accordingly he was expelled and deprived of all his honours and estates in 1102.
He m. before 9 Sep. 1087, Agnes, da. and h. of Guy, COUNT OF PONTHIEU, and Ada, his wife, and became, in her right, on the death of her said father in 1101, COUNT OF PONTHIEU. He is sometimes said to have m. secondly a da. of Robert FITZHAMON. He fought at the battle of Tinchebray in 1106 on behalf of Robert of Normandy, escaping therefrom but was taken prisoner 4 Nov. 1112, by Henry I. at Bonneville-sur-Tougues, aud was confined at Cherbourg and the next year (1113) at Wareham, co. Norfolk, where, probably, he d. soon afterwards, but (says Henry of Huntingdon in his letter to Walter), "no one knew after he was in prison, whether he was alive or dead, and report was silent as to the day of his death."
A footnote to the above entry adds some colourful detail:
"The character ot this extraordinary man, whose great talents distinguished him from most of the turbulent nobles of the age, seems to have inspired all contemporary historians with horror. Henry of Huntingdon says 'he was a very Pluto, Megæra, Cerberus, or anything you can conceive still more horrible," and give details of his cruelties surpassing those narrated by
Ordericus Vitalis.' Brooke (uncontradicted by Vincent) says "He was a man very outrageously given and most cruel to his own children aud hostages, whose eyes (with his own hands) be plucked out."
Succeeded his brother, Hugh (the 2nd Earl) in 1098.
Footnotes
[1]
The Complete Peerage, GE Cokayne, 1st Edition, Volume 7 (S-T), London (1896); Shrewsbury, pages 133-148