Ousted King of Leinster, Diarmait Mac Murchada (Dermot MacMurragh), sought help in regaining his kingdom from Cambro-Norman mercenaries.

In the autumn of 1171, King Henry II of England decided to lead a military expedition to Ireland to establish his control over both the Norman warlords and the Irish.

[3] 1261.5 Very destructive war was waged against the Galls(foreigners) this year by Fingen son of Domnall Mac Carthaig and his kinsmen.

Mac Carthy attacked and defeated them; and in this contest were slain eight barons and five knights, besides others of the English nobles, as also John son of Thomas and Barry More.

1261.4 A great war was waged, and numerous injuries were committed, by Finghin, son of Domhnall Mac Carthaigh, and his brothers, against Foreigners in this year.