Gailenga

Gailenga was the name of two related peoples and kingdoms found in medieval Ireland in Brega and Connacht.

Francis John Byrne, in agreement with Eoin MacNeill, believes that "they were vassal tribes of fighting men whom the Connachta and Ui Neill ... planted on the lands they conquered."

Rawlinson B 502 or Rawlinson B 512 contains the following genealogy: Léocán m. Laidgneáin m. Máeláin m. Éicnich m. Dúnchada m. Cináeda m. Léocáin m. Donngaile m. Conchobair m. Moínaich m. Máel Mórda m. Adamra m. Dechraich m. Dergscáil m. Leae nó oe m. Cormaicc [Gaileang] m. Taidg m. Céin m. Ailella Auluimm.

They themselves dominated smaller tribes, and have some claim to be considered an over-kingdom, as recognised in the twelfth century when their lands were absorbed into the diocese of Achonry.

The baronies of Gallen in Mayo and Leyney in Sligo, along with Corrand and Coolavin in the Curlew Mountains, lloming over the fertile plain of Moylurg, into which the Ui Briuin Ai were to expand, were crowded with small tribes, some of whom are intimately connected with the origin legends of the Connachta."