Excerpts from Books and Wikipedia
"At the age of six, Christina succeeded her father [King Gustavus Adolphus] upon his death at the Battle of Lützen, but began ruling the Swedish Empire when she reached the age of 18 in 1644. Christina is remembered as one of the most learned women of the 17th century. She was fond of books, manuscripts, paintings, and sculptures. With her interest in religion, philosophy, mathematics and alchemy, she attracted many scientists to Stockholm, wanting the city to become the "Athens of the North." She was intelligent, fickle and moody. She caused a scandal when she decided not to marry and in 1654 when she abdicated her throne and converted to Roman Catholicism. . . . Christina's financial extravagance brought the state to the verge of bankruptcy, and the financial difficulties caused public unrest after ten years of ruling." [Wikipedia] In 1650, Rene Descartes died of pneumonia in Sweden while working as a mathematics tutor for the young queen Kristina who was then 24 years old. [Furtado: 1001 Days]