Mac Siúrtáin

The family take their name from the Norman knight, Jordan de Exeter, whose descendants became known as Mac Siúrtáin - the Gaelic form of Jordan - and were based in County Mayo.

The descendants of Jordan de Exeter settled in Connacht, mainly in what is now County Mayo.

The territory they conquered, Gailenga (later known as the barony of Gallen), was the southern part of Luighne (also known as Sliabh Lugha), whose lords were the clan Ó Gadhra.

The de Exeters expelled the Ó Gadhras into Coolavin, County Sligo, while the clan Ó hEaghra retained the name Luighne for their territory to the north.

Only the chief of the clan was entitled to be called de Exeter.