It was probably constructed by the Anglo-Norman Roger de Pitres, the first post-Norman Conquest Sheriff of Gloucestershire, as a simple motte and bailey castle during the reign of William the Conqueror (1066–1087), when sixteen houses were demolished to make way for it.
Walter of Gloucester,[3] Sheriff of Gloucestershire, succeeded his father Roger de Pitres as Constable of the castle.
Before 1113 Walter built a new castle west of Barbican hill on a former garden of Gloucester Abbey, overlooking the River Severn.
[3] Part of the castle had been being used as a gaol by 1185 and it was probably then the official county gaol, as it certainly was by 1228,[3] and Eleanor of Brittany, niece of King John and cousin of Henry III with a better claim to the throne according to primogeniture and thus becoming a state prisoner, had been briefly imprisoned there during the reign of John, from 1222 to 1223, and from 1237 to 1238,[5] while in 1222 to accommodate her the castle temporarily moved all its prisoners elsewhere.
[3] In December 2015, the castle's foundations were uncovered by archaeologists who were investigating the Gloucester Prison site ahead of a new development.