Christina of Sweden (reigned 1632 – 1654)
Swedish queen Christina became Queen Regnant in 1632 at the age of six and assumed the duties of the crown in 1644. The Polish king, who had a reasonable claim to the throne, threatened her reign from the start. Despite the need for an heir to secure the succession, and keep Poland from claiming the throne, Christina never married. Instead she appointed her cousin, Charles Gustavus, as heir. Succession aside, she passionately supported science and the arts, hoping to create an “Athens of the North.” She was instrumental in negotiation a peace treaty and ending the Thirty Years War, but was uneasy serving as ruler and had converted to Catholicism, which was banned in Sweden. Christina abdicated the throne in 1655, moved to Rome, and focused on science and culture.