A people which was unable to offer effectual resistance when the Assyrian levies invaded their country, and which had no means of retaliating upon their foe or making him suffer the evils that he inflicted, was naturally tempted to save itself from molestation by the payment of an annual tribute, so purchasing quiet at the expense of honor and independence.

Towards the close of the ninth century B.C.the Medes seem to have followed the example set them very much earlier by their kindred and neighbors, the Persians, and to have made arrangements for an annual payment which should exempt their territory from ravage.

It is doubtful whether the arrangement was made by the whole people.

The Median tribes at this time hung so loosely together that a policy adopted by one portion of them might be entirely repudiated by another.

Most probably the tribute was paid by those tribes only which boarded on Zagros, and not by those further to the east or to the north, into whose territories the Assyrian arms has not yet penetrated.
No further change in the condition of the Medes is known to have occurred until about a hundred years later, when the Assyrians ceased to be content with the semi-independent position which had been hitherto allowed them, and determined on their more complete subjugation.