Complex sentence: Llywelyn's victory allowed him to claim the title of prince of Gwynedd and, in turn, prince of Wales; ejected from his lands, Dafydd went to live in England and died in 1203.
Split into simpler sentences: Llywelyn's victory allowed him to claim the title of prince of Gwynedd and, in turn, prince of Wales. Ejected from his lands, Dafydd went to live in England and died in 1203.