As the beachhead of an Irish colony and later as the anchor of the Guenodotia kingdom, the island represented a strategically significant place in the power struggles of Wales.
The island was partially romanized after the Roman campaign to kill the druids ended in a massacre there in the first century. This included Roman roads as well as other aspects of culture.
The island was colonized by the Irish during the late fourth century in response to Roman forces retreating and consolidating their borders. It would have a British presence there until the late fifth century with Einion. His dynasty would eventually drive the Irish off.
- "Rhyfelfawr Arthur"