CASTLES

THREE royal castles guarded the central Thames valley, Windsor, Wallingford, and Oxford, though this last was founded by a leading baron with the Conqueror's consent and came into royal hands during the twelfth century. Wallingford and Oxford were prominent in the war between Stephen and Matilda, and while Oxford had fallen into disrepair by the early fourteenth century, Wallingford was maintained for residential purposes for a further century. To the west, the Severn estuary was guarded by the royal fortresses at Bristol, Gloucester, and St Briavels. Bristol fell into decay during the fifteenth century and Gloucester from the close of that era, but though St Briavels lapsed from its primary purpose as an administrative centre for the royal forest of Dean, it was maintained for its court and prison function until the mid-nineteenth century.

The region shows a broad span of private castles, chronologically, tenurially, and structurally, with three of them retaining substantive evidence. Those of modest defensive capacity such as Ascott d'Oilly, Stratton Audley, and Deddington had been abandoned before the close of the fourteenth century. The stronghold of the Giffards at Brimpsfield was destroyed on the orders of Edward II in 1322 to join the earlier abandoned earthworks and adulterine sites scattered across the region. Nor does anything survive of Banbury Castle, first erected by bishop Alexander of Lincoln in about 1130 as the administrative centre of the bishop's extensive estates in the area. It was almost entirely rebuilt during the early fourteenth century in concentric form with drum towers and a massive gateway and so maintained until the Civil War.