The Austrian army played a crucial role in Napoleon's decisive defeat during the War of the Sixth Coalition. Often considered a staid, hidebound institution, the army showed considerable adaptation in a time that witnessed a revolution in the art of war. In particular, changes made after defeat in the War of the Fifth Coalition demonstrate the modernity of the army. It embraced the key features of the new revolutionary way of war, including mass mobilization, a strategy of annihilation, and tactics based on deep echelonment, mobility, and the flexible use of varied formations. While the Austrians did not achieve the compromise peace they desired in 1814, this represented a political failing rather than a military one. Nevertheless, the Austrian army was critical in securing the century of general European peace that lasted until the dawn of the Great War.