Peter III of Russia
During the reign of Peter III of Russia (January to July, 1762), Mikhail Vorontsov was the most powerful man in Russia, as his niece Elizaveta Vorontsova became the Emperor's mistress. Peter's wife Catherine, alarmed by her husband's plans to divorce her and marry Elizaveta Vorontsova, deposed her husband, with great help from her bosom friend, Yekaterina Romanovna Vorontsova-Dashkova, the wife of Prince Dashkov and Elizaveta's own sister.