In the 13th century the Braose family were Lords of Gower and held the castle as part of their extensive land holdings and titles, including other castles on Gower and in the Welsh Marches.
The de Braose dynasty could afford to rebuild Oystermouth castle in stone.
A high curtain wall was built, internal buildings added, a chapel, basements, three storey residential buildings with fireplaces and garderobes on each floor.
The castle had every residential feature necessary for living in some comfort and was also refortified cleverly.
Towards the end of the century Oystermouth rather than Swansea Castle became their principal residence.
Edward I paid a brief visit here in December 1284.

By 1331 the Lords of Gower were living elsewhere and the castle declined in importance in the 14th century.

The daughter of the last de Breos Lord, Aline de Breos, who improved the chapel making it one of the finest in any castle in south Wales, later married John de Mowbray, and the Lordship of Gower including the castle at Oystermouth passed to the de Mowbrays through this marriage, and then to the Herbert family, and finally the Somersets, who became successive Marquis of Worcester and finally Dukes of Beaufort.
In the 13th century the Braose family were Lords of Gower and held the castle as part of their extensive land holdings and titles, including other castles on Gower and in the Welsh Marches. The de Braose dynasty could afford to rebuild Oystermouth castle in stone. A high curtain wall was built, internal buildings added, a chapel, basements, three storey residential buildings with fireplaces and garderobes on each floor. The castle had every residential feature necessary for living in some comfort and was also refortified cleverly. Towards the end of the century Oystermouth rather than Swansea Castle became their principal residence. Edward I paid a brief visit here in December 1284.
By 1331 the Lords of Gower were living elsewhere and the castle declined in importance in the 14th century.
The daughter of the last de Breos Lord, Aline de Breos, who improved the chapel making it one of the finest in any castle in south Wales, later married John de Mowbray, and the Lordship of Gower including the castle at Oystermouth passed to the de Mowbrays through this marriage, and then to the Herbert family, and finally the Somersets, who became successive Marquis of Worcester and finally Dukes of Beaufort.
Oystermouth Castle