Anna Margareta von Haugwitz (1622-1673) was a German noblewoman. She married the Swedish count Carl Gustav Wrangel at the age of 18 after a month-long engagement. Her English-language Wikipedia article, with links to Swedish- and German-language Wikipedia articles, is here.
The spiral-patterned column à la Bernini add an interesting note to this portrait.
From fuckyeahhistorycrushes.tumblr.com. (That's the name...)