The Constable of Chester was a mediaeval hereditary office held by the Barons of Halton. The functions of the Constable are unclear, possibly they related to the custody of Chester Castle (built in 1070 by Hugh d'Avranches, 1st Earl of Chester), as was the main function of most mediaeval constables, but Sanders (1960) says the office-holder was constable for the entire County Palatine.[1]