The castle was built between 1313 and 1325 for Thomas Earl of Lancaster, nephew of King Edward II. The isolated location of the castle probably reflects Thomas's need to protect himself both from Scottish raids, and from the wrath of the King, with whom he had many disagreements, in particular, over the influence of Piers Gaveston, the King's favourite. Eventually, a group of Lords, led by Thomas, captured and executed Gaveston. Although the king finally pardoned the barons, Thomas, who continued to rebel against the king, was executed in 1322.