The bare essentials were not in doubt. Harpagus, commander of the Median army, and most prominent of the clan chiefs, had deserted to Cyrus, leading a rebellion in mid-battle, and taking Astyages captive. But why such treachery? Because – so the story went – Harpagus, a close kinsman of Astyages, had simultaneously been bound by the most terrible ties of obligation to the King of Persia.
