The central epic of the Ulster Cycle
The Tain Bo Cuailnge is the centrepiece of Old Irish literature, often called the Irish Iliad. It opens with a marital audit: Queen Medb of Connacht and her husband Ailill compare their possessions and find them equal in everything except Ailill's white-horned bull, Finnbennach. Hearing that the district of Cooley in Ulster holds its match, the brown bull Donn Cuailnge, Medb first tries to borrow it, then raises the armies of four provinces to take it. Ulster meanwhile lies under Macha's curse, its men struck down in crisis with the weakness of a woman in labour, punishment for a king who once forced the pregnant goddess to race his horses. Only Cu Chulainn, seventeen and exempt, stands in the invaders' path.
Invoking the right of single combat at the fords, he kills Medb's champions one by one through a winter while she cheats and probes and the war goddess Morrigan meddles. The epic's most mourned episode is the three days' fight at the ford between Cu Chulainn and his foster-brother Ferdiad, who exchange healing herbs and food each night until the gae bolga ends it, and the victor laments over the body. When the Ulstermen finally rise, Medb's host is routed, but the brown bull has already been driven west. The two bulls then fight their own war: Donn Cuailnge tears Finnbennach apart, scatters pieces of him across Ireland into place-names, and dies of the effort, leaving both provinces bereaved of the prize.
The tale survives in three recensions, the earliest in Lebor na hUidre, the Book of the Dun Cow, written about 1106. The Book of Leinster copy ends with the scribe's Latin verdict: he will not vouch for the stories, some of which are 'the deceptions of demons' and some 'poetic figments'. Thomas Kinsella's 1969 translation carried the epic to modern readers.
