(c.1173–1240), prince of Gwynedd, where he consolidated his power before moving into neighbouring territories, having his conquests recognised by Henry III under the Treaty of Worcester in 1218. He continued to extend his dominance in north and mid Wales, and although he did not adopt the title ‘Prince of Wales’, in 1230 he adopted the style ‘Prince of Aberffraw and Lord of Snowdon.’ His last years were marked by his efforts to ensure the succession of his son Dafydd.