Zahhak and Kaveh the blacksmith

In Ferdowsi's Shahnameh, Zahhak begins as a prince who can be flattered. Ahriman, the spirit of evil, comes to him in disguise, first as a counsellor who persuades him to kill his own father, then as a cook who wins his favour with rich meat. As a reward, the cook asks only to kiss the prince's shoulders. Where his lips touch, two black serpents grow. Cut them off and they grow back. Then Ahriman returns, this time as a physician, with a prescription: feed the snakes human brains. Every day two young men are to be killed for them. Zahhak, now ruler of Iran after Jamshid's fall, reigns for a thousand years in Ferdowsi's telling, and the land is emptied of its sons.

The tyranny ends with an ordinary man. Kaveh, a blacksmith, bursts into Zahhak's court because his sons have been taken for the serpents; in the Shahnameh he says only one of his many sons remains. Zahhak, anxious about a prophecy of his downfall, has just made his nobles sign a declaration that he is a just king. He hands Kaveh's son back and asks the blacksmith to sign too. Kaveh reads it, tears it up, and walks out. In the bazaar he takes the leather apron that blacksmiths wear at the forge, fixes it to the tip of a spear, and calls the people to follow him. This becomes the Derafsh-e Kaviani, Kaveh's banner, later adorned with jewels by the kings who carried it. Kaveh does not take the throne himself. He leads the people to Fereydun, the rightful heir, who defeats Zahhak.

Fereydun does not kill him. In the Shahnameh, the angel Sorush tells him to bind Zahhak instead, and he is chained inside Mount Damavand, the great volcano north-east of Tehran. Evil is not destroyed; it is contained. The Avesta tells an older version, in which Azhi Dahaka is a three-headed dragon slain or overcome by Thraetaona, the figure who becomes Fereydun. Somewhere between the two, the dragon became a man with dragon's shoulders.

Why it still matters

Zahhak is the Persian shorthand for tyranny, and Kaveh for the people's refusal. Poets, cartoonists and political movements of every stripe have reached for the leather banner. Damavand, snow-capped and visible from Tehran on clear days, still carries the story.