Sophia Von Kielmansegg, Countess Of Darlington

Sophia Charlotte von Kielmansegg, Countess of Darlington and Countess of Leinster (1675–1725), was a German-born courtier. She was a half-sister of George I of Great Britain and maintained a close relationship with him. In 1714, shortly after the Hanoverian succession, she relocated to England and became an influential figure at his court.

Her parentage includes Clara Elisabeth von Meisenbuch, who was married to Franz Ernst, Count von Platen-Hallermund, a court official. Clara Elisabeth was also the mistress of Ernest Augustus, Elector of Brunswick-Lüneburg. Ernest Augustus was married to Sophia of the Palatine and was in the line of succession for the kingdoms of England and Scotland. Sophia Charlotte was regarded as an illegitimate daughter of Ernest Augustus, sharing a familial connection to George I through this relationship.

In 1701, she married Baron Johann Adolph von Kielmansegg (1668–1717). They had two children: Georg Ludwig (1705–1785) and Maria Sophia Charlotte (1703–1782). Maria Charlotte married Emanuel Howe, 2nd Viscount Howe, and had issue.

At the court of George I in London, Sophia von Kielmansegg competed for influence alongside Melusine von der Schulenburg, Duchess of Kendal, who was the king's mistress. Her titles included Countess of Darlington, in the Peerage of Great Britain, bestowed in 1722, and Baroness of Brentford. She had previously been granted the title Countess of Leinster in the Peerage of Ireland in 1721. Her blood relationship to George I was not widely recognized in Britain, leading to the misconception that she was also a royal mistress, similar to the Duchess of Kendal. An incident involving her access to the king resulted in the dismissal of a confectioner who was caught making indecent remarks about her and the king. She often sought the king’s favor through gift-giving, especially during the period of the South Sea Bubble.

She died in London on 20 April 1725.

She was nicknamed "the Elephant and Castle" upon her arrival in England in 1714, a reference to her size. According to Horace Walpole, she was a very large woman, with a notably imposing figure. Walpole described her as having fierce black eyes beneath arched eyebrows, cheeks spread with crimson, and an expansive neck that appeared to merge with her lower body, emphasizing her stature and physical presence.