This chapter explores the importance of legitimacy in the life and politics of Empress Catherine II of Russia (1729–96). Born as Princess Sophia Augusta Fredericka of Anhalt-Zerbst, she married the future Tsar Peter III of Russia in 1745. Having overthrown her husband in 1762 without any dynastic claim to the throne herself, she needed to prove her legitimacy through other means. Aware of her shaky claim in a country where rulers with much stronger ties to the throne had been deposed with ease, she was careful not to lose necessary support among the most influential groups in her realm. Indeed, one major justification for her coup d’état had been to keep Russian traditions and culture alive. Catherine also considered herself an enlightened monarch with the authority to exert absolute power for the benefit of the nation. Yet during the course of her reign she abandoned reforms under the pressure of domestic politics and troubled by upheavals against authority in Russia and elsewhere. In general, the chapter argues that Catherine II governed in an autocratic manner in consideration that her legitimacy was not grounded in hereditary claims, but in her ability, and hers alone, as the one individual most capable to rule.