An enterprising warrior would doubtless have followed up the defeat of the invader by attacking him in his own country before he could recover from the severe blow dealt him; but the aged Assyrian monarch appears to have been content with repelling his foe, and made no effort to retaliate.
Cgaxares, the successor of the slain Median king, effected at his leisure such arrangements as he thought necessary before repeating his predecessor's attempt.

When they were completed--perhaps in B.C.

632--he led his troops into Assyria, defeated the Assyrian forces in the field, and, following up his advantage, appeared before Nineveh and closely invested the town.

Nineveh would perhaps have fallen in this year; but suddenly and unexpectedly a strange event recalled the Median monarch to his own country, where a danger threatened him previously unknown in Western Asia.
When at the present day we take a general survey of the world's past history, we see that, by a species of fatality--by a law, that is, whose workings we cannot trace--there issue from time to time out of the frozen bosons of the North vast hordes of uncouth savages--brave, hungry, countless--who swarm into the fairer southern regions determinedly, irresistibly; like locusts winging their flight into a green land.

How such multitudes come to be propagated in countries where life is with difficulty sustained, we do not know; why the impulse suddenly seizes them to quit their old haunts and move steadily in a given direction, we cannot say: but we see that the phenomenon is one of constant recurrence, and we therefore now scarcely regard it as being curious or strange at all.