Fenian Cycle

The cycle also contains stories about other famous Fianna members, including Diarmuid, Caílte, Oisín's son Oscar, and Fionn's rival Goll mac Morna.

In the introduction to his Fianaigecht, Kuno Meyer listed the relevant poems and prose texts between the seventh and fourteenth centuries[3] and further examples can be adduced for later ages: The Finn's father Cumhal is discussed as the leader of the Fianna in Fotha Catha Cnucha ("Cause of the Battle of Cnucha"), his elopement and the conception of Finn mac Cumhal[10] is the cause of the battle, in which Cumhal is killed by Goll mac Morna.

[12] The onomastics surrounding Almu, the stronghold of the Fianna is also discussed here, quoting from the Metrical Dindsenchas on this landmark.

[10][a][b] And it is stated that when Finn grew old enough, he received the estate of Almu as compensation (éraic) from his grandfather, who was partly to blame for Cumhal's death.

Between the birth of Oisin and the Battle of Gabhra is the rest of the cycle, which is very long and becomes too complicated for a short summary.

Eventually, the High King Cormac dies and his son Cairbre Lifechair wants to destroy the Fianna because he does not like paying the taxes for protection that the Fianna demanded, so he raises an army with other dissatisfied chiefs and provokes the war by killing Fionn's servant.