Frances Thynne was a wealthy heiress who grew up at Longleat, the estate of her paternal grandfather Thomas Thynne, 1st Viscount Weymouth. In 1713, she married Algernon Seymour, then Earl of Hertford. Lord Hertford was a book and music lover and spent much time with his uncle Heneage Finch, Earl of Winchilsea (Anne Finch's husband). The couple had two children. Lady Hertford was appointed to serve as lady-in-waiting to Caroline of Ansbach, Princess of Wales, and soon became involved in scholarly patronage. When she was not in residence at court, Lady Hertford spent much time at the family country estate of Marlborough Castle in Wiltshire (known as The Mount). In 1748, her husband succeeded as 7th Duke of Somerset and Frances then became known as Duchess of Somerset. Her works included letters, a fragmentary political journal, commonplace-books, and poems, some of which circulated in manuscript and drifted into print in her lifetime. She wrote two poems about Yarico, a native American woman brutally betrayed by her white English lover, which appeared anonymously in A New Miscellany: Being a Collection of Pieces of Poetry (1725). The Story of Inkle and Yarrico was handsomely published, with its companion piece, as Attempted in Verses by The Right Hon. the Countess of **** in 1738. Her letters were edited posthumously in two volumes by William Bingley in 1805.