The church is the reputed burial place of Iestyn ap Gwrgant who is said to have become a religious at Llangennith after being deposed by the Norman Robert Fitzhamon in 1090 .
Iestyn ap Gwrgant is the last ruler of the Welsh kingdom of Morgannwg .
The church is the reputed burial place of Iestyn ap Gwrgant , the last ruler of the Welsh kingdom of Morgannwg , who is said to have become a religious at Llangennith after being deposed by the Norman Robert Fitzhamon in 1090 .