ABSTRACT
With the decision to go to war made, Archduke Charles planned the main Austrian advance along the upper Danube River. The 1st through 5th Corps, along with the 1st Reserve Corps, would advance north of the river out of Bohemia. The 6th Corps and the 2nd Reserve Corps would advance south of the river from a starting position on the Bavarian border. When reports arrived that the French were beginning to concentrate in the Augsburg area, the specter of an unprotected Vienna being taken by a rapid advance along the south bank of the Danube caused Charles to rethink his plans. Accordingly, he shifted the main body of his troops south of the Danube to the Inn River line on the border with Bavaria. While this countered the perceived threat, the decision cost the Austrians one month of critical time. Even so, by 10 April 1809, the army was in position.
