Ailill mac Máta

Ailill mac Máta is the king of the Connachta and the husband of queen Medb in the Ulster Cycle of Irish mythology. He rules from Cruachan (Rathcroghan in County Roscommon).

The sagas explain mac Máta as a matronymic: his mother is Máta Muirisc, daughter of Mága, of the Fir Ol nÉcmacht, a tribal grouping of Connacht, through whom he claimed the throne of the Connachta. His father is Rus Ruad, king of the Laigin, whose other sons include Cairbre Nia Fer, king of Tara, Find Fili, who succeeded him as king of the Laigin, and in some texts Cathbad, chief druid of Conchobar mac Nessa of the Ulaid. The Táin Bó Cúailnge says Medb chose him as husband, ahead of Find, Cairbre and Conchobar, because he alone among them was without meanness, jealousy or fear.

A late saga, Cath Boinde, tells a different story. It says Ailill was the grandson of Medb's sister Ele, and came to Cruachan as a young child to be raised by Medb, who was already reigning there with her then-husband Eochaid Dála. He grew up to be a fine warrior, and became chief of Medb's bodyguard, and her lover. Eochaid tried to expel Ailill from Connacht, but Medb would not allow it. He then challenged him to single combat, and lost. Ailill then became Medb's husband and king of the Connachta.

Ailill and Medb had seven sons, all called Maine. They originally had other names, but after Medb asked a druid which of her sons would kill Conchobar, and received the reply "Maine", they were all renamed as follows:

The prophecy was fulfilled when Maine Andoe went on to kill Conchobar, son of Arthur, son of Bruide — not Conchobar mac Nessa of the Ulaid, as Medb had assumed the druid meant. Medb and Ailill also had a daughter, Findabair.

Ailill led the Táin Bó Cúailnge (cattle raid of Cooley) against the Ulaid, an expedition intended to steal their prize bull Donn Cúailnge. The prologue to the later version of the Táin says this was a result of a dispute between Ailill and Medb over who was wealthier. Their wealth was equal, except for one thing: the bull Finnbhennach, who was born into Medb's herd, but thought it was beneath his dignity to be owned by a woman and transferred himself into Ailill's ownership. The only bull his equal in Ireland was Donn Cúailnge, so it was decided to acquire him for Medb to restore their equality.

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