Queen Christina arrived in Rome with much fanfare in 1655. She was met by the College of Cardinals at the Porto del Popolo, newly redecorated in her honor by Bernini, and there, also, she could read Pope Alexander VII's personal greeting which is still inscribed over the gate: "Felice faustoque ingressui - 1655" -- "may your entry be happy and propitious".
Christina, once in Rome, turned out to be imperious and capricious -- she once took a practice shot with a Castel Sant'Angelo cannon without bothering to aim it, and hit the door of the Villa Medici. (The dented door is still there, and the supposed cannon ball is now atop the fountain in front of the entrance.) She became the darling and the scandal of Roman society and was a patron both of the arts (especially Archangello Corelli, whose style revolutionized the playing of string instruments, and Alessandro Scarlatti, whose first Opera she subsidized and produced) and of alchemy.
Not everyone in Rome was enamoured of the Queen. The Vatican had made her a Catholic icon and ignored her eccentricities (including, a lot of cross-dressing), but a famous Pasquinade had it that she was "queen without a realm, Christian without a faith, and woman without shame". Some modern literary analysts see her as the inspiration for the Queen of Hearts in Alice in Wonderland.
After her death, and against her own expressed wishes, she was interred beneath the high altar at St. Peter's in the Vatican.
Christina on the Internet:
Catholic Encyclopedia: http://www.newadvent.org/cathen/03722a.htm
Christina as Alchemist: http://www.levity.com/alchemy/queen_christina.html
Paper from Oregon State U. Philosophy Department: http://osu.orst.edu/instruct/phl302/philosophers/wasa.html
Greta Garbo -- 1933 Queen Christina Movie:
More Christina links: http://pages.ancientsites.com/~Torrey_Philemon/christina/chrislinks.htmsites listed above.