| Guithelin | |
|---|---|
| King of Britain | |
| Predecessor | Gurguit Barbtruc |
| Successor | Marcia (Regent); Sisillius II |
| Spouse | Marcia |
| Issue | Sisillius I |
| Father | Gurguit Barbtruc |
Guithelin was a legendary king of the Britons as accounted by Geoffrey of Monmouth. He became king after the death of Gurguit Barbtruc[1] and reigned approximately 379 BC.
He ruled liberally and temperately for his life. His Queen consort was an artisan and noblewoman named Marcia; when he died, his wife took over the government as regent for their son, Sisillius II.[2]