Ó Gadhra

Ó Gadhra or O'Gara is an Irish surname which originated in the kingdom of Luighne Connacht. Variants include Garry, Geary, Gerry, and .

The first O'Gara's were descendants of the Gailenga people. Their descendants were located in Sliabh Lugha (later known as the barony of Gallen), the southern part of the territory ruled by the Kings of Luighne Connacht.

In the 13th century they were expelled from the area (by the Clan Mac Siúrtáin) and moved to Cul Ui Fionn, later known as the barony of Coolavin, County Sligo.

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