Christina, in Swedish, Kristina (1626-89), queen of Sweden (1632-54). The sole heir of Gustav II Adolph, Christina succeeded her father at the age of six, a regency under Axel Oxenstierna ruling until she assumed full royal power in 1644. Throughout her reign, she attempted to increase the authority of the Crown, and in this she was supported by the lower estates against the nobility and the Council of the Realm. The Thirty Years' War, however, had led Sweden into an economic crisis that Christina was unable to resolve. Highly intelligent, she was interested in intellectual pursuits and was influenced by the French philosopher René Descartes, who lived in Stockholm in 1649-50. Christina never married. In 1654 she abdicated the throne, had her cousin Charles recognized as her successor, and announced that she had converted to Roman Catholicism. Self-exiled, she lived the rest of her life in Rome.