Roger de Mumbezon

Roger de Montbegon (Roger de Mumbezon, Roger de Mont Begon) (died 1226) was a landowner in northern England (especially or particularly Lancashire), Baron of Hornby, and one of the Magna Carta sureties.

There is a scholarly debate about his place in the list of sureties. J. C. Holt takes it that Matthew Paris made a mistake in replacing his name with 'Roger de Mowbray'. According to the record publicized by the National Society Magna Charta Dames and Barons, Roger abandoned the sureties and therefore Roger de Mowbray (younger brother of William de Mowbray, another surety) was substituted for him; this probably explains Matthew Paris' alleged error.

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