On February 9, 1744, aged 15, she came to Russia at the invitation of Empress Elizaveta Petrovna as the bride of the heir to the throne, Peter Feodorovich.

They married in St. Petersburg on August 21, 1745, and she was christened into the Orthodox Church as Ekaterina Alexeevna. Industrious, highly intelligent and strong-willed, she quickly mastered the Russian language. A reader of historical and philosophical works, she entered into correspondence with some of the greatest minds in Europe, including Voltaire.

On June 28, 1762, with the support of the Imperial Guard, she overthrew her husband Peter III. She was crowned Empress of All Russia on September 22, 1762, in the Dormition Cathedral of the Moscow Kremlin. Her rule was one of the most prosperous periods of the Russian Empire.

She undertook a wide range of internal political reforms, waged two successful wars against the Ottoman Empire and occupied vast territories on Russia's southern boundaries, eventually advancing the country's border to the Black Sea.

She died on November 6, 1796, and was buried in the Cathedral of the St. Peter and St. Paul Fortress in St. Petersburg.