Anna Leopoldovna (Russian: А́нна Леопо́льдовна; 18 December 1718 – 19 March 1746), born as Elisabeth Katharina Christine von Mecklenburg-Schwerin and also known as Anna Carlovna (А́нна Ка́рловна), was regent of Russia for a few months in 1740 and 1741 during the minority of her infant son Emperor Ivan VI.

Elisabeth Katharina Christine was the daughter of Catherine, the sister of the Russian empress Anna, and of Karl Leopold, the duke of Mecklenburg-Schwerin. Catherine separated from Elisabeth's father and the two escaped to Russia in 1722. Catherine was considered for the imperial throne in 1730 but her sister Anna was chosen instead. In 1733, Elisabeth converted to the Russian Orthodox Church and given the name Anna Leopoldovna, which made her acceptable as an heir to the throne. In 1739, she married Anthony Ulrich (1714–1776), son of Ferdinand Albert, Duke of Brunswick-Wolfenbüttel. He had lived in Russia since 1733 so that she could get to know him.

On 5 October 1740, the empress Anna adopted their newborn son Ivan and proclaimed him heir to the Russian throne. On 28 October, just a few weeks after this proclamation, the empress died, leaving directions regarding the succession and appointing her favourite Ernest Biron, Duke of Courland, as regent.

Biron, however, had made himself an object of detestation to the Russian people. After Biron threatened to exile Anna and her spouse to Germany, she had little difficulty working with Field Marshal Burkhard Christoph von Münnich to overthrow him. The coup succeeded and she assumed the regency on 8 November, taking the title of Grand Duchess. Field Marshal Münnich personally arrested Biron in his apartment, where the formerly tyrannical Biron ingloriously begged for his life on his knees. She knew little of the character of the people with whom she had to deal, knew even less of the conventions and politics of Russian government, and speedily quarrelled with her principal supporters.

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