A great battle was fought, probably somewhere in Adiabene, in which the Medes were completely defeated: their whole army was cut to pieces; and the father of Cyaxares was among the slain.

Such was the result of the first Median expedition against Nineveh.

The assailants had miscalculated their strength.

In their own mountain country, and so long as they should be called upon to act only on the defensive, they might be right in regarding themselves as a match for the Assyrians; but when they descended into the plain, and allowed their enemy the opportunity of manoeuvering and of using his war chariots, their inferiority was marked.

Cyaxares, now, if not previously, actual king, withdrew awhile from the war, and, convinced that all the valor of his Medes would be unavailing without discipline, set himself to organize the army on a new system, taking a pattern from the enemy, who had long possessed some knowledge of tactics.