Settling himself at the newly-conquered city of Babylon, he resolved to employ his generals against the rebels, and in this way to gauge the strength of the outbreak, before adventuring his own person into the fray.

Hydarnes, one of the Seven conspirators, was sent into Media with an army, while Dadarses, an Armenian, was dispatched into Armenia, and Vomises, a Persian, was ordered to march through Assyria into the same country.
All three generals were met by the forces of the pretender, and several battles were fought, with results that seem not to have been very decisive.

Darius claims the victory on each occasion for his own generals; but it is evident that his arms made little progress, and that, in spite of several small defeats, the rebellion maintained a bold front, and was thought not unlikely to be successful.

So strong was this feeling that two of the eastern provinces, Hyrcania and Parthia, deserted the Persian cause in the midst of the struggle, and placed themselves under the rule of Xathrites.

Either this circumstance, or the general position of affairs, induced Darius at length to take the field in person.