Hortense Mancini, Duchesse Mazarin, was born in Rome on 6 June 1646 into a family of aristocrats. She was the fourth of five Mancini sisters, who along with two of their female Martinozzi cousins, were known at the court of Louis XIV as the Mazarinettes. Her mother was the sister of Giulio Mazarini, the Italian cardinal and papal emissary who rose to power in France and became chief minister to Louis XIV.
He arranged her marriage to the wealthy but abusive nobleman, Armand-Charles de La Porte de la Meilleraye in 1661. She left him and her four children in 1668. Hortense moved to Chambéry where she was given the protection of Carlo Emanuele II di Savoia until his death in 1675. There she wrote her memoirs.
She then settled in London at the court of Charles II as his mistress. Residing at St James Palace, Whitehall, she cultivated a salon frequented by French exiles. In 1689, her husband brought suit against Hortense to force her to return to France and resume conjugal life. Although the French court decided in his favour, Hortense chose to remain in London where she faced financial hardship. With the ascension of William and Mary to the throne, she was out of favour at the English court. Having lost her divorce case and her Royal patrons, Mancini moved to Chelsea in 1693, acquiring a home on Paradise Row. There she died in July 1699.