Cath Gabhra (English: The Battle of Gabhair or Gowra) is a narrative of the Fenian Cycle of Irish mythology.
[1] Cath Gabhra exists in many versions, and is referenced often in other works, including poems about Cairbre Lifechair in the Book of Leinster and in the long narrative Acallam na Senórach.
However, the fianna and Fionn mac Cumhaill demand a large tribute for the marriage, and Cairbre decides their power has corrupted them.
He raises a vast army from Ulster, Leinster, and Connacht, which is joined by the faction of the fianna loyal to Fionn's enemy Goll mac Morna.
Cairbre's forces ultimately triumph, and the only survivors of the fianna are Oisín and Caílte mac Rónáin, who live long enough to recount their tale to Saint Patrick two centuries later, according to Acallam na Senórach.