Deganwy Castle has been occupied since Roman times. It was built in the 6th Century as the residence of Maelgwyn Gwynedd (Arx Decantorum 822). The Norman, Robert of Ruddland built a castle there. The area was recovered by the Welsh and in 1200 it passed to Llewelyn Fawr. In 1210, the Welsh destroyed the castle after an English conquest. The Norman Earl of Chester refortified it with timber but Llewelyn regained in 1213.
In 1241 Llewelyn's son, David, burnt it down. In 1244 Henry II ordered the Castle of 'Ganwock' be fortified. It was attacked by Llewelyn the Last in 1257 and finally it was destroyed in 1263. There was also a town charter in 1252.
Original Index No. F0001.