Ilbert de Lacy

de Lacy (Laci, Lacie, Lascy, Lacey) is the surname of an old Norman family which originated from Lassy, Calvados. The family took part in the Norman conquest of England and the later Norman invasion of Ireland. The name is first recorded for Hugh de Lacy (1020–1085). His sons, Walter and Ilbert, left Normandy and travelled to England with William the Conqueror. The awards of land by the Conqueror to the de Lacy sons led to two distinct branches of the family: the northern branch, centred on Blackburnshire and west Yorkshire was held by Ilbert's descendants; the southern branch of Marcher Lords, centred on Herefordshire and Shropshire, was held by Walter's descendants.

Until 1399, the northern branch of the family held the great Lordship of Bowland before it passed through marriage to the Duchy of Lancaster. They were also Barons of Pontefract and later Earls of Lincoln.

The southern branch of the family became substantial landholders in the Lordship of Ireland and was linked to the Scottish royal family; Elizabeth de Burgh, great granddaughter of Walter de Lacy, married Robert the Bruce, King of Scotland.

The sons of Hugh de Lacy, Lord of Lassy (c.1020 – 27 March 1085), Ilbert and Walter jointly held the Norman lands that were held of the Bishop of Bayeux. They participated in the Norman conquest of England. While there is evidence that Ilbert fought at William's side at Hastings, there is no record of Walter fighting at Hastings. Ilbert was a major participant in the Harrying of the North (1069–70) which effectively ended the quasi-independence of the region through large-scale destruction that resulted in the relative "pacification" of the local population and the replacement of local Anglo-Danish lords with Normans. In return, he received vast grants of land in West Yorkshire, where he built Pontefract Castle.

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