 Harliston was born in Humberstone, Lincolnshire, and brought up in the household of Richard, Duke of York.Three years previously the castle of Mont Orgueil in Jersey had been captured by a French noble, Pierre de Brézé, Compte de Maulevrier, who had since held the eastern half of that island against Philip de Carteret, Seigneur of St Ouen.In 1468 Edward IV sent Harliston and his fleet to Guernsey, as part of a plan to invade France and recover Normandy.