Cyrus the Great had absorbed the Medes, the Lydians and the Babylonians, and his northeastern frontier was still open. The Eurasian steppe was a highway for mounted raiders, so he wanted the Massagetae lands as a buffer and the Central Asian trade routes as a prize. His opening move was not an army but a marriage proposal to their widowed queen, Tomyris, which was the cheapest instrument of annexation available in the sixth century BC: absorb a kingdom through a wedding, install your own governors, and inherit its warriors for the next campaign. She read it exactly as it was and refused. When he brought his forces to the Araxes River and began building a pontoon bridge, she sent a measured warning telling him to rule his own kingdom and leave her to hers. He crossed anyway.

His heavy infantry was built for phalanxes, sieges and set-piece battles, none of which work against people who have no cities and shoot composite bows from horseback at a hundred yards. His vanguard was cut apart. So he switched from conventional war to a trick, laying out a lavish banquet in camp with jars of undiluted wine and withdrawing his veterans, leaving the feast guarded by his weakest troops. The Massagetae drank fermented mare’s milk, not concentrated grape wine, and had no cultural protocol for it and no metabolic defense against it. Tomyris’s son Spargapises took the camp, sat down to the spoils, and woke in chains having lost a third of his mother’s army.

• Spargapises begged to be unbound, and the moment Cyrus freed him he killed himself rather than serve as a hostage against his own mother.
• Tomyris called Cyrus a coward who had won with poison rather than skill, and swore an oath by the sun that if he did not leave she would give him more blood than he could drink.
• She won the battle, found his body, cut off his head and pushed it into a skin filled with blood, turning the appetite that defined his career into the manner of his death.
• Ctesias, a Greek doctor at the Persian court with access to their records, tells it completely differently: a different enemy, war elephants, and Cyrus dying peacefully in his tent after three days arranging his succession. Herodotus needed a lesson about hubris. Persia needed a founder who died in good order.