| Iestyn ap Gwrgant King of Morgannwg | |
|---|---|
| Reign | 1081–1093 |
| Coronation | 1081 |
| Predecessor | Caradog ap Gruffydd |
| Hereditary | Extinct |
| Born | 1014 Morgannwg, Wales |
| Died | 1093 Rhiwbina, Glamorgan, Wales |
| Consort | Constance ferch Cadwgon |
| Wife |
|
| Issue | Catrin ferch Iestyn Madog ap Iestyn Caradog ap Iestyn Rhys ap Iestyn Nest ferch Iestyn Gwenllian ferch Iestyn |
| Welsh | Brythonic Branch |
| House | Morgannwg |
| Father | Gwrgant ab Ithel |
| Mother | MissVerch Gwerystan |
Iestyn ap Gwrgant [ˈjɛstɪn ap ˈgʊrgant] (or Jestyn ap Gwrgant) (English: Iestyn, son of Gwrgant) (1014–1093) was the last ruler of the Welsh kingdom of Morgannwg, which encompassed the counties of Glamorgan and Monmouthshire.[1][2]