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A summary of the epic Irish saga, the Táin Bó Cúailnge, or Cattle Raid of Cooley, as translated by Cecile O’Rahilly from the Book of Leinster.
This story begins not on a battlefield, but in a bedroom.
Queen Medb of Connacht and her husband, King Ailill, engage in some late-night pillow talk to determine whose wealth is superior.
After comparing gold, jewelry, and vast herds, they find their fortunes perfectly matched—with one devastating exception.
Ailill possesses the Finnbhennach, a magnificent white-horned bull.
Medb has no equal to it, as the only bull of its caliber, the Donn Cúailnge (the Brown Bull of Cooley), resides in the province of Ulster.
Driven by pride and a refusal to be outshone, Medb assembles a massive army to march on Ulster and take the Brown Bull by force.
Her timing is calculated; she knows the men of Ulster are currently incapacitated by the “Pangs of Ulster,” a divine curse that leaves them with the weakness of a woman in labor for five days and four nights.
Only one warrior stands exempt from the curse: the seventeen-year-old Cú Chulainn, a demi-god of unparalleled ferocity.
As Medb’s host crosses the border, they find their progress halted at every river and ford.
Cú Chulainn wages a relentless guerrilla war, picking off scouts and commanders with his sling and spear.
Eventually, he strikes a bargain with Medb: the army will advance only as fast as he can be defeated in single combat.
Each day, Medb sends her greatest champions to face him at the ford; each day, Cú Chulainn slaughters them.
The conflict grows increasingly tragic.
Medb eventually manipulates Cú Chulainn’s foster-brother and dearest friend, Ferdiad, into fighting him.
Their three-day duel is the emotional heart of the epic—a brutal struggle between duty and love that ends with Cú Chulainn using the legendary Gáe Bulg, a barbed spear of certain death, to kill his brother.
Heartbroken and exhausted, Cú Chulainn is eventually joined by his father, the sun god Lugh, who heals his wounds while the warrior sleeps.
As the Pangs of Ulster finally lift, King Conchobar mac Nessa rallies the Ulaid.
The forces meet in a climactic, gore-drenched battle at Gáirech and Ilgáirech.
The carnage is absolute, ending only when Cú Chulainn enters his “warp-spasm,” a terrifying physical transformation into a monstrous engine of war.
He drives the Connacht forces back across the Shannon, sparing Medb’s life only after she retreats.
Though Medb successfully captures the Brown Bull during the chaos, the victory is hollow.
Upon reaching Connacht, the Brown Bull of Cooley meets the White-Horned Bull of Ailill.
The two beasts engage in a cosmic struggle that ranges across the entire island.
The Brown Bull eventually gores his rival to death, but exhausted by the fight, he wanders back toward Ulster, his heart bursting as he collapses and dies on the journey home.
The war, sparked by a dispute over status, leaves both sides devastated and the prizes of the conflict dead in the dirt.