William de Percy
The Cartulary of Whitby Abbey states that Hugh d'Avranches (later 1st Earl of Chester) and William de Percy arrived in England in 1067, one year after the Norman Conquest.[5] He appears in Domesday as a great landowner, holding 30 knight's fees, including some lands which had belonged to a Saxon lady, whom, "as very heire to them, in discharging of his conscience," he afterwards married.Hugh Lupus, on becoming Earl of Chester, transferred to him his great estate of Whitby in the North Riding of Yorkshire, where he re-founded the Abbey of St. Hilda's, and appointed his brother Serlo de Percy the first prior.Following the rebellion of Gospatric Earl of Northumbria, and the subsequent Harrying of the North, much territory in northern England and the Earldom of Chester were granted to Hugh d'Avranches, who had been instrumental in the devastation.Percy married an English noblewoman called Emma de Port, her epithet presumably came from her landholdings at Seamer, a once thriving manor in North Yorkshire.