The first "Grande Armée" consisted of six corps under the command of Napoleon's marshals and senior generals. When the Austrian and Russian armies began preparations to invade France in late 1805, the "Grande Armée" was quickly ordered across the Rhine into southern Germany, leading to Napoleon's victories at Ulm and Austerlitz. The French army grew as Napoleon seized power across Europe, recruiting troops from occupied and allied nations; it reached its peak of one million men at the start of the Russian campaign in 1812, with the Grande Armée reaching its height of 413,000 soldiers, who would take part in the invasion.