The young Owain ap Gruffydd was possibly fostered at the home of David Hanmer, a rising lawyer shortly to be a justice of the Kings Bench, or at the home of Richard FitzAlan, 3rd Earl of Arundel. Owain is then thought to have been sent to London to study law at the Inns of Court. He probably studied as a legal apprentice for seven years. He was possibly in London during the Peasants' Revolt of 1381. By 1383, he had returned to Wales, where he married David Hanmer's daughter, Margaret, started his large family and established himself as the Squire of Sycharth and Glyndyfrdwy, with all the responsibilities that entailed.