In front of him was the Inn, a broad and deep river protected by strongly fortified places; behind him John of Werth, a bitterly hostile country, and the river Isar.

On his left would be Wallenstein himself marching across the Bohemian forest.

When, therefore, he learned that Duke Bernhard was hastening on from the Isar towards Passau he put his army in motion and marched southward, so as to place himself in the left rear of the duke.

This movement Duke Bernhard heard of just when he arrived in sight of Passau, and he instantly recognized the extreme danger of his position, and perceived with his usual quickness of glance that to be caught before Passau by Wallenstein and John of Werth would be absolute destruction.

A moment's hesitation and the Swedish army would have been lost.