General Notes

William de Ferrers, 3rd Earl of Derby, rebelled against Henry II and marching at the head of the Leicestershire men (19th Henry II) upon Nottingham, then kept for the king by Reginald de Luci, got possession of the town which he sacked, putting the greater part of the inhabitants to the sword and taking the rest prisoners. He was soon afterwards, however, reduced to submission and obliged to surrender to the crown his castles in Tutbury and Duffield, which were demolished by order of the king. His lordship m. Sibilla, dau. of William de Braose, Lord of Abergavenny and Brecknock, by whom he had issue. [Sir Bernard Burke, Dormant, Abeyant, Forfeited, and Extinct Peerages, Burke's Peerage, Ltd., London, 1883, p. 196, Ferrers, Earls of Derby]


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There is substantial confusion over his name. See The Complete Peerage Vol. 4, p 193 for an account. Personally, I feel there could have been two brothers, William and Robert, Robert being the Earl and when he died at Acre his nephew William [son of his brother William] succeeded, but no documents support this theory! In The Complete Peerage vol. XIV, p. 250 it is suggested that Robert is a fabrication by Vincent, Earl of Ferrieres. [Brian Tompsett, Directory of Royal Genealogical Data, http://www.dcs.hull.ac.uk/cgi-bin/gedlkup/n=royal?royal04492]