They assisted the Northumbrians to expel Tostig, of the house of Godwin, in 1065 and Morcar was chosen earl by the rebels. Harold, Tostig's brother, consented to this extension of the power of the Mercian house. In spite of this concession, and the help which he gave them against Tostig and Harald Hardråde, the two brothers left him to fight alone at Hastings.
After trying to secure the crown for their own house, they submitted to William, but lost their earldoms. They attempted to raise the North in 1068, and failed ignominiously. They were pardoned, but Morcar afterwards joined Hereward in the Isle of Ely (1071), while Edwin perished in attempting to raise a Welsh rebellion. Morcar died in prison; at what date is unknown.
See EA Freeman, Norman Conquest and William Rufus, vol. i.
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