At the beginning of the 12th century, Wales consisted of numerous independent principalities and kingdoms, which were often in conflict with each other. The Anglo-Norman kings did not directly engage in the conquest of Welsh lands, leaving this task to the Lords of Marches, border territorial units with extensive autonomy. As part of this gradual conquest of southern Wales, in 1107 king Henry I gave the Gower peninsula to Henry de Beaumont, Earl of Warwick, who invaded the area and immediately built a castle in Swansea. He also distributed the land on the peninsula to his supporters, giving the area around Mumbles to William de Londres, a Norman knight who was also the owner of the Ogmore castle. Shortly after receiving new lands, around 1106, William built the Oystermouth Castle on the hill above Swansea Bay. This original building was probably a timber – earth ringwork.
In 1116, Gruffydd ap Rhys raided the Gower peninsula and burnt the castle. The Normans rebuilt it, but in 1136 Gower was again attacked by the Welsh, this time by Hwyel ap Maredudd, and it is possible that Oystermouth was destroyed again. Subsequent attacks on the peninsula, this time Rhys from Dehebarth, took place in 1189 and 1192, although the castle survived in both cases. In 1203, the English king John granted Gower to John de Braose, but the Oystermouth Castle remained the property of the Londres family. The male line of this family ended in 1215, and the castle passed into the hands of William de Braose. At about the same time, the Oystermouth Castle was again attacked by the Welsh under the command of Rhys Grug and Rhys Leunan, the allies of prince Llywelyn ap Iorwerth. In 1220, the Welsh were eventually expelled from the peninsula, and Henry III returned the Gower barony to John de Braose, who rebuilt the castles at Swansea and Oystermouth.
The de Braose family was one of the main Anglo-Norman families, and Oystermouth became their main residence at the end of the 13th century. At that time, the castle was rebuilt, most likely by William de Braose, into a stone stronghold. William was a powerful magnate at the court of Edward I and hosted the king at Oystermouth in 1284. He served Edward in both the Welsh and Scottish wars, and his significant achievement was the capture of the Welsh rebel William Cragh and participation in the victorious battle of Falkirk in 1298.
In 1331, the castle passed on to John de Mowbray, who was the first owner who live in a different place than Oystermouth. The stronghold fell into disrepair and probably therefore played a small role in the Welsh rebellion of Owain Glyndŵr, who occupied the Gower peninsula between 1403 and 1405. Over the next centuries, the castle often changed owners, but none of them undertook to rebuild it.
The castle was erected on a plan of polygon with defensive walls tapering in the south-east direction, where the entrance to the stronghold was located. It was secured by a gate from the second half of the 13th century, consisting of two flanking horseshoe towers. Compared to other similar designs from this period (for exemple Caerphilly), the Oystermouth gatehouse was simpler and less fortified. It had only one door and one portcullis, and it did not have rooms on the sides of the passage. The rooms on the first floor of the gatehouse were accessible through the entrances from the side of the inner ward.
In the triangular ward from the north-east side there was a chapel, and the northern part was occupied by a keep. In the 13th century, it was extended from the north, which increased its size more than twice and provided the main living rooms in the castle. The original entrance to it was on the level of the first floor, but already in the thirteenth century, a new entrance in the gound floor, around which the porch was later erected, was pierced. Communication between the floors was provided by a staircase in the north-western part of the keep, and a long corridor gave the opportunity to move to the north-west range. The main living room was on the first floor. The great hall was located in the southern part, and the private room (solar) on the top floor from the north. The hall could be open to the roof. With the addition of new buildings around the keep, new doors were introduced to improve communication. In this way, you could easily go to the north-west range and the chapel on the south-east side.
The chapel building from the 14th century consisted of a well-lit chamber with a fireplace and a latrine on the first floor. Ground floor probably had an economic role, and the chapel itself was on the second floor. It was lit from the side of the ward by two large ogival windows with traceries. It contained two opposite, vaulted niches in the north and south walls, supporting chimney ducts. In the southern niche, fragments of wall polychromy are preserved, while in the south-eastern corner of the chapel – piscina.
The remaining buildings of the castle are north-west range containing, among other, a prison, a rectangular building at the west defensive wall, which probably served an economic function and a rectangular building on the eastern side. By the southern curtain there was an oblong, rectangular building of the castle’s kitchen.
The castle has survived to modern times in a state of well-preserved ruin with a full circumference of defensive walls and walls of all buildings inside. The most noteworthy lack are the flanking gate towers which no longer exist. Only the holes on the floor beams are visible in their back walls. The castle has recently undergone a thorough renovation, thanks to which all its parts have been made available to the public. Unfortunately, the opportunity was not without the insertion of modernist glass – concrete – metal elements biting the historic substance. The castle is open from April 1 to September 30 from 11:00 to 17:00.
Kenyon J., The medieval castles of Wales, Cardiff 2010.
Website castlesfortsbattles.co.uk, Oystermouth castle.