The Menapii are the only known Celtic tribe specifically named on Ptolemy’s AD 150 map of Ireland, where they located their first colony — Menapia — on the Leinster coast circa 216 BC. They later settled around Lough Erne, becoming known as the Fir Manach, and giving their name to Fermanagh and Monaghan. Mongán mac Fiachnai, a 7th-century King of Ulster, is the protagonist of several legends linking him with Manannán mac Lir. They spread across Ireland, evolving into historic Irish (also Scottish and Manx) clans.