The only monastic foundation which survived the Conquest was Peterborough. At the time of the Domesday Survey the boundaries of Northamptonshire were approximately the same as the present day. Northamptonshire is first mentioned by name in the "Historia Eliensis", in connection with events which occurred at the close of the 10th century. At the time of the Domesday survey the chief lay-tenant in Northamptonshire was Robert, earl of Mortain, whose fief escheated to the crown in 1106. The estates of William Peverel, founder of the Abbey of St James at Northampton, also escheated to the crown in the 12th century.