 It was said that at the time of the fall of Richard III, Harliston had thought to make himself "Lord of the Islands" under the protection of the French and the Duchess, Margaret de Burgundy, but had been prevented by the diligence of the inhabitants, not those who had wanted him for their captain-general, mostly the supporters of Henry Tudor.By the irony of fate, Harliston was himself besieged in the castle because, faithful to the House of York, he refused to hand over the keys to the emissary of Henry VII.He was forced to capitulate after a siege of six months, and he retired to Flanders.