Iestyn
Iestyn is the name of the following people:
- Rhydderch ap Iestyn († 1033), King of Gwent and Morgannwg in South Wales
- Iestyn ap Gwrgan († 1093), King of the Welsh Kingdom of Morgannwg
- Caradog ap Iestyn († before 1147), the first Welsh Lord of Afan
