His father Count Johann Rudolf von Buol-Schauenstein (1763–1834) from 1816 until 1823 chaired the Austrian delegation to the Bundesversammlung of the German Confederation.

He joined the Austrian foreign service and served successively as envoy to Baden at Karlsruhe (1828–1838), to Württemberg at Stuttgart (1838–1844), to Sardinia-Piedmont at Turin (1844–1848), to Russia at Saint Petersburg (1848–1850), to the German ministerial conference at Dresden 1850/51, and to the United Kingdom at London (1851–1852).

He became an increasingly close associate of the Austrian Minister-President, Prince Felix of Schwarzenberg, and when Schwarzenberg suddenly died in April 1852, Buol succeeded him as foreign minister, although not as Premier, as the young Emperor Franz Joseph himself now took a more direct role in directing cabinet affairs than he had previously.

Furthermore, the geographical positions involved meant that in any war with Russia, Austria, even if allied with France and Britain, would bear the brunt of the fighting.

As the conflict dragged on into 1855, Buol sent another ultimatum to Russia, this time demanding that it accede to the French and British terms, or face a war with Austria.

This time the Russians, now under Tsar Alexander II, acceded, and preliminary peace accords were signed at Vienna later that year.