Built during the reign of William the Conqueror, and later owned by Robert FitzHamon, it became an important royal castle and was the scene of several imprisonments and executions.

Among the recipients was Robert FitzHamon, who having thus gained a large swathe of Gloucestershire, including Bristol Castle, founded the feudal barony of Gloucester.

His eldest daughter and heiress Mabel FitzHamon married Robert, 1st Earl of Gloucester, illegitimate son of King Henry I.

As his chronicler reported: "On one side of it, where it is considered more exposed to siege and more accessible, a castle rising on a vast mound, strengthened by wall and battlements, towers and divers engines, prevents an enemy's approach.

The rebellion was put down the following year, and William was punished by having Bristol Castle confiscated and taken under royal control.

From 1224, Eleanor of Brittany was strictly confined to the castle under relatively comfortable conditions, with accommodation in the keep, almost to her death in 1241, except for sometime between 1225 and 1227 when she was presumably locked in her tower or room.

[9] The two young sons of Dafydd ap Gruffydd, the last princes of Gwynedd, were imprisoned for life in Bristol Castle after Edward I's conquest of Wales in 1283.

In the other court is an attractive church and many domestic quarters, with a great gate on the south side, a stone bridge and three ramparts on the left bank leading to the mouth of the Frome.

[12] By the sixteenth century the castle had fallen into disuse, but the City authorities had no control over royal property and the precincts became a refuge for lawbreakers.

The western section is a dry ditch and a sally port into the moat survives near St Peter's Church.