He entered the imperial cavalry in 1787. His courage at the Battles of Hohenlinden (1800) and Ulm (1805) saved many Austrian lives, and he was then appointed vice-president of the supreme imperial war cabinet in Vienna, where he was responsible for raising a popular militia to defend Austrian homelands. As general of cavalry he fought at the unsuccessful Battle of Wagram (1809), after which Austria made peace with Napoleon in the Treaty of Schönbrunn. Schwarzenberg negotiated (1810) the marriage between Napoleon and Marie-Louise, daughter of the Austrian emperor, who in 1811 agreed to assist Napoleon in his forthcoming campaign against Russia. After Napoleon’s failure to capture Moscow (1812) Schwarzenberg skilfully withdrew his troops back to Austria. Next year, when Austria joined Russia, Prussia, and Sweden to fight Napoleon (August 1813), he was appointed commander-in-chief of the Austrian Army and was the senior commander at the Battle of Leipzig in October. He attended the Congress of Vienna and then retired.