sentences:  Following Llywelyn's defeat at the hands of Edward I of England in 1277 Owen returned to Wales alongside his father whose lands had been restored.They soon became embroiled in a border dispute with Llywelyn which was one of the catalysts for a renewed campaign by the princes of Gwynedd against English domination.In 1284, following the Conquest of Wales by Edward I, the "de la Pole" family surrendered their princely pretensions, but received back their principality in "free barony" as the marcher lordship of Powys.