[Ir., of the Liffey; Liffeylover].
An ard rí [high king] of Ireland in the Fenian Cycle, son of Cormac mac Airt, and antagonist of Fionn mac Cumhaill and his men. At the beginning of Cairbre's reign Fionn's Fianna has power to rival the king's. When Cairbre's daughter Sgiamh Sholais [beauty of light] is to be married, the Fianna demand a tribute of twenty gold ingots, which, they say, is customarily paid to them on these occasions. Outraged, Cairbre seizes this opportunity to rally his allies and crush the Fianna. In doing so he splits apart the rival factions of the clans Baíscne and Morna, the latter joining him. In the final conflagration, described in Cath Gabhra [The Battle of Gabhair/Gowra], the Fianna are crushed but Cairbre, mortally wounded by Oscar, puts a spear through Oscar's heart, thus dispatching the greatest Fenian warrior. In other stories the battle is named Cnámross. His brother is Dóel, and his most notable son is Eochu Doimlén, father of the rapacious three Collas; another son was Fiachu Sraibthine. The story of his conception by Cormac upon Eithne Tháebfhota is told in Esnada Tige Buchet [The Melodies of Buchet's House].