Edmund Crouchback

Type Figure Region Kingdom of England Time 1245–1296 Also known as 1st Earl of Lancaster、Edmund of Lancaster

Edmund Crouchback (1245–1296), second son of Henry III, was Earl of Lancaster and Leicester and served as Lord Lieutenant of Ireland;…

Timeline

1291–1295London · Kingdom of EnglandIn the early 1290s Edmund, as the king's own brother, took part in English governance and coordination among the nobility. He held a wide network of vassals in his northern estates and was a key royal prince on whom Edward I relied, playing an important role in preparations for the Scottish wars and in maintaining domestic order.
1296Bedford · HertfordshireEdmund died at Bedford, Hertfordshire, in 1296, aged about fifty-one. His earldoms of Lancaster and Leicester and his broad estates passed to his eldest son Thomas, making the House of Lancaster a weighty force on the English political stage.

Edmund of Lancaster: A Study of Constitutional History — W. E. Rhodes (1913)
The Oxford Dictionary of National Biography: Edmund, first earl of Lancaster — J. R. Maddicott (2004) https://www.oxforddnb.com/