Ptolemy's map of c. 150 AD does in fact list a people called the Nagnatae as living in the west of Ireland.

Some are of the opinion that Ptolemy's Map of Ireland may be based on cartography carried out as much as five hundred years before his time.

The Connachta were a group of dynasties who claimed descent from the three eldest sons of Eochaid Mugmedon: Brion, Ailill and Fiachrae.

They took their collective name from their alleged descent from Conn Cétchathach.

Their younger brother, Niall Noigiallach was ancestor to the Uí Néill.