I . (d. 1203), a son of Prince Owen Gwynedd (d. 1169), came into prominence as a leader of the Welsh during the expedition of Henry II. in 1157. In 1170 he became lord of Gwynedd (i.e. the district around Snowdon), but some regarded him as a bastard, and Gwynedd was also claimed by other members of his family. After fighting with varying fortunes he sought an ally in the English king, whom he supported during the baronial rising in 1173; then after this event he married Henry's half-sister Emma. But his enemies increased in power, and about 1194 he was driven from Wales by the partisans of his half-brother Llewelyn ab Iorwerth. The chronicler Benedictus Abbas calls David rex, and Rhuddlan castle was probably the centre of his vague authority.