Anna Leopoldovna (1718 - 18 March, 1746), also known as Anna Karlovna, regent of Russia for a few months (1740 - 1741) during the minority of her baby son Ivan, was the daughter of Catherine (sister of Empress Anna) and of Charles Leopold, the Duke of Mecklenburg-Schwerin. In 1739 she married Anthony Ulrich (1714 - 1776), son of Ferdinand Albert, Duke of Brunswick-Wolfenbüttel. Wikipedia
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