Sophia Dorothea of Hanover (26 March [O.S. 16 March] 1687 – 28 June 1757; German: Sophie Dorothea von Hannover) was Queen in Prussia and Electress of Brandenburg during the reign of her husband, King Frederick William I, from 1713 to 1740. She was the mother of Frederick the Great (King Frederick II of Prussia).
At the time of Sophia's birth, her father was merely the son of a German prince, Ernest Augustus, Duke of Brunswick-Lüneburg. It was not until 1701 that the Act of Settlement placed him, through his mother, in line to inherit the throne of Great Britain. Sophia was 27 years of age, and had already become the Queen in Prussia and a mother of many children by the time her father became King George I of Great Britain in 1714.