The greatest war in Irish mythology — and the one bull that caused it
The Táin Bó Cúailnge — the Cattle Raid of Cooley — is Ireland’s equivalent of the Iliad. It is the longest, grandest, most epic story in the entire Irish literary tradition, built around one of the most extraordinary dramatic premises in world mythology: a war started by two people arguing in bed about who was richer. What follows involves a queen with an army, a hero defending his province single-handed, and a bull so magnificent that kingdoms went to war over it.
The Pillow Talk
Queen Medb of Connacht and her husband Ailill were lying in bed one night, comparing their wealth. They went through everything — their gold, their land, their servants, their herds — and found that they were exactly equal in everything. Except one thing: Ailill had a magnificent white-horned bull named Finnbhennach that had left Medb’s herd to join his, considering it beneath its dignity to be owned by a woman.
Medb refused to be outdone. She sent messengers all over Ireland to find a bull that could match Finnbhennach, and learned of one: the Donn Cúailnge, the Brown Bull of Cooley, in Ulster.
She asked to borrow it. The negotiations began well — and then one of her messengers got drunk and told the Ulster king that Medb would have taken the bull by force anyway. The deal collapsed. Medb raised her army and marched on Ulster.
The Weakness of Ulster
Ulster’s warriors were cursed. The goddess Macha — one of the aspects of the Morrígan — had been forced to race against horses while heavily pregnant, and in her fury at the indignity she had cursed the men of Ulster to suffer labour pains at the moment of Ulster’s greatest need. At the moment Medb’s army crossed the border, every Ulster warrior except Cú Chulainn collapsed in agony. He was exempt because he was not fully of Ulster — his divine blood protected him.
Cú Chulainn alone stood between Medb’s vast army and Ulster.
The Single-Combat Defence
Under the rules of war — or by negotiation with Medb — Cú Chulainn fought the Connacht army one champion at a time, in single combat, each day. As long as he was fighting a single champion, the army had to halt. It was the only way one man could delay thousands.
He fought for weeks — exhausted, wounded, surviving on divine aid sent secretly by his father Lugh, facing heroes who had been specifically sent to kill him. One of them was his best friend: Fer Diad, his foster-brother from their training days under Scáthach.
Fer Diad
The four-day fight between Cú Chulainn and Fer Diad at the ford is the emotional heart of the Táin. They had been inseparable friends. They greeted each other with grief the morning of the first day. They fought with equal honour each day and tended each other’s wounds each night. On the fourth day, Cú Chulainn used the gáe bolg and killed the man he loved. He mourned him more bitterly than any other enemy he had ever defeated.
The Bulls’ War
Medb got the Brown Bull in the end — briefly. The Donn Cúailnge and Finnbhennach fought each other across all of Ireland in a battle so vast that it reshaped the landscape. The Brown Bull killed the white bull — and then it went mad from its wounds and rage and died.
The war ended with nothing. Medb had her army, but no bull. Ulster had its warriors back. Cú Chulainn had survived — for now. The two sides agreed to peace, and Medb and Cú Chulainn faced each other one last time without fighting. It was not yet time.
Key facts about the Táin
- Irish title: Táin Bó Cúailnge (“The Cattle Raid of Cooley”)
- Cause: Queen Medb’s jealousy over her husband’s prize bull; sought Ulster’s Brown Bull to match it
- Ulster’s curse: Macha’s curse — all Ulster warriors suffered labour pains at the moment of crisis
- Sole defender: Cú Chulainn — exempt from the curse due to his divine blood
- His tactic: Daily single combat — while fighting one champion, the entire army had to halt
- Most painful fight: Four days of combat against Fer Diad — his best friend and foster-brother
- Fatal weapon used: The gáe bolg — to kill Fer Diad on the fourth day
- The bulls’ fate: Donn Cúailnge killed Finnbhennach — then went mad and died; the war gained nothing
- Cycle: Ulster Cycle
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