In 1715 she had married LandgraveFriedrich I of Hesse-Kassel, whose counsel she constantly sought in political matters. She even wanted him to officially become co-regent, but this was not allowed, and in stead she abdicated in his favour after just one year of reign. Friedrich succeeded her on the Swedish throne as King Frederick I. Queen Ulrika Eleonora died of smallpox in 1741 after a childless marriage. The reigns of Ulrika Eleonora and her husband saw the birth of the era of Swedish history that is traditionally called the Age of Liberty, where the monarch had to give up most of his power to the aristocracy.