The hill on which the Deganwy Castle was erected was occupied already in the Iron and Roman era. It was especially important due to the exposed location of the Conwy River and access from the Irish Sea, which made this area an easy target for pirates and invaders. In the 6th century, probably Maelgwn Gwynedd, the ruler of the kingdom of Gwynedd, had his residence there. This fortress burned in 812 after a lightning strike, and after rebuilding, it was then destroyed during the Saxon invasion in 822.
In 1080, Robert of Rhuddlan built a castle on the hill. He searched for the possibility of expanding his lands and used the splits between the Welsh people for this purpose, and Deganwy was to secure the newly acquired territories. In 1093 he left the castle to repel the Welsh invasion, but paid it with his life. According to tradition, his head was fastened to the mast of one of the invader’s ships. The next few decades of the castle’s history are unknown, it is only known that at the end of the 12th century it was in the hands of the Welsh. This situation did not change at the beginning of the thirteenth century, when Llywelyn ap Iorwerth, prince of Gwynedd, supported English king John in the struggle with the lords of the marches. Only when in 1211 Llywelyn objected to John, and he sent an English army, the Welsh left the castle after it was burned. Two years later Llywelyn was able to return to the destroyed stronghold, because the king was unable to maintain troops in Wales. He rebuilt the castle, which became one of its key objects, because in 1228 he imprisoned one of his sons. Llywelyn’s death in 1240 prompted the Welsh to destroy the castle again to prevent its use by the English.
In the years 1245-1254, king Henry III of England significantly expanded and strengthened the castle. In spite of this, there were frequent attacks by the Welsh, and finally the siege and capture of Deganwy by Llywelyn ap Gruffudd in 1263. His territorial achievements were approved when, four years later, Henry III sealed the Montgomery Treaty, recognizing the Llywelyn authorities over Wales. In 1282, after the defeats of two Wars of Independence and the death of Llywelyn ap Gruffudd, the whole of North Wales along with the Deganwy Castle was under the control of the English. King Edward immediately began the building program of castles to strengthen English rule. Destroyed Deganwy, however, was not re-used, Edward preferred to erect a new fortress and the town of Conwy, which located on the river, could be supplied by sea, if necessary. Deganwy Castle was dismantled for building materials, and what remained was completely ruined.
The castle from the mid-13th century was erected on two hills connected by a wall of fortified outer bailey. The main part was built on the western top, which was crowned with a large, round tower, flanking the entrance to the castle from the side of the outer bailey. It probably acted as a keep. Right next to the tower was the main, rectangular building with a great hall. In addition, the upper ward was defended by the horseshoe tower on the north-west side. On the eastern hill there was a so-called Mansel’s Tower, in a horseshoe shape with a small bulge from the south. The castle was to be surrounded by a defensive wall, going from the Mansel’s Tower to the south-west and north-west towards the west hill, but only its southern part was completed in stone. The northern part was largely fortified with a timber palisade. The entrance to the castle was provided by a south gate consisting of two towers flanking the passage between them. A similar gate was planned on the north side, but it was probably never completed.
The castle has not survived to the present day, you can see only small relics of walls scattered in various places. As these areas were abandoned and not built in early modern times, two hills stand out today in the landscape, allowing you to imagine the layout of a medieval castle.
Kenyon J., The medieval castles of Wales, Cardiff 2010.
Website castlesfortsbattles.co.uk, Deganwy castle.