After the Norman Conquest of England by William the Conqueror in AD 1066, the land in the East Riding was granted to followers of the new Norman king and ecclesiastical institutions. When some of the northern earls rebelled, William retaliated with the Harrying of the North which laid waste to many East Riding villages. The land was then distributed among powerful barons, such as the Count of Aumale in Holderness and the Percy family in the Wolds and the Vale of York. These lay lords and ecclesiastical institutions, including the monasteries, continued to improve and drain their holdings throughout the Middle Ages to maximise the rents they could charge for them.