Having wintered on the banks of the Gyndes in a mild climate, where tents would have been quite a sufficient protection to his army, he put his troops in motion at the commencement of spring, crossed the Tigris apparently unopposed, and soon came in sight of the capital.

Here he found the Babylonian army drawn out to meet him under the command of Nabonadius himself, who had resolved to try the chance of a battle.

An engagement ensued, of which we possess no details; our informants simply tell us that the Babylonian monarch was completely defeated, and that, while most of his army sought safety within the walls of the capital, he himself with a small body of troops threw himself into Borsippa, an important town lying at a short distance from Babylon towards the south-west.

It is not easy to see the exact object of this movement.

Perhaps Nabonadius thought that the enemy would thereby be obliged to divide his army, which might then more easily be defeated; perhaps he imagined that by remaining without the walls he might be able to collect such a force among his subjects and allies as would compel the beleaguering army to withdraw.