An Ealdorman, or Alderman, was the prior magistrate of a British shire in A. D. 900 to A. D. 1100. Ealdormanship was the highest form of nobility, up until after A. D. 1100, when ranks such as Barons where introduced. The Ealdormen where the commanders of the armies in the surrounding district (the shire). The Old English word for Ealdormen is Ældormenn, meaning, "older men".

See also: ealdormancy