Czar Peter III was considered unstable; the marriage was unhappy, and Catherine spent much of her time in political intriguing, and extramarital affairs. In 1762 a palace coup overthrew her unpopular husband, and she was proclaimed empress.

Catherine II, with the advise of her lover Potemkin, carried out an energetic foreign policy. A series of Russo-Turkish wars erupted as a result of which the Russian Empire was extended to the Black Sea. In the West, Russia expanded into Poland after the three partitions of that unfortunate nation.

Domestically great cultural advances were made among the nobility under Catherine's rule, but in 1774 she suppressed the popular rebellion led by Pugachev, and later actively persecuted members of the progressive-minded nobility.