General Notes

At the time of the Conquest, the Castle of Mitford, in Northumberland, was held by Sir John de Mitford, whose only daughter and heiress, Sibella Mitford, was given in marriage by the Conqueror to a Norman knight of the name of Richard Bertram, and from this alliance sprang the Lords Bertram of Mitford. [Sir Bernard Burke, Dormant, Abeyant, Forfeited, and Extinct Peerages, Burke's Peerage, Ltd., London, 1883, p. 52, Bertram, Barons Bertram, of Mitford]