He joined up as a sergeant in the Semyonovsky Regiment of Russia's Imperial Guard in 1781 aged 12. Between 1782 and 1786 he studied at the Protestant faculty in Strasbourg to perfect his French and German language skills. He admired Goethe and Friedrich Schiller and wrote the latter a letter in German when he was only 17. He also keenly studied music and dance, gaining him the nickname "Boris-Vestris" after the French dancer Auguste Vestris. He continued his education as a sub-lieutenant at the École militaire in Paris during the last years of the Ancien Regime; he did not meet Napoleon Bonaparte who left the school in October 1785. Two weeks after the Storming of the Bastille a written order came to the Golitsyns to patrol in the city as guards. The correspondence of the elder of the Golitsyn brothers attests to his deep interest in analyzing and comprehending the events of the French Revolution. Boris made critical remarks on the proposals of Dubois-Crancé in the Assembly. In 1791 Catherine the Great had ordered the whole family to leave Paris and get back to Moscow, but they first visited Rome, where the brothers were portrayed by Hugh Douglas Hamilton.