The Queen's Diadem, by C. J. L. Almqvist
Once upon a time, I was a comparative literature major and I took classes in Scandinavian literature. Sometimes I read the book in Danish (or Norwegian, or Swedish, because the attitude is why translate when the languages are so close? Just figure it out already) and then wrote the paper in Danish too, probably badly. I read some really great books, but that was a long time ago and I forgot quite a bit. I still have the books, though, and so I put them on my Classics Club list to re-read. English only, this time. The Queen's Diadem, or Drottningens juvelsmycke, was one of those books. I wrote a paper and everything, but that was in 1995 or something and I'd forgotten all but the central symbol of the novel.
I found a weird and fantastic tale. I can't believe I forgot this!
C. J. L. Almqvist was one of the greatest voices in Swedish/Scandinavian literature and a leading Romantic writer--this would be in the 1830s. He worked in many genres, writing drama, essays, novels, and poetry. Reading the biographical note, I was reminded of Pushkin (though with less duelling). He was very interested in politics, especially in the status of women, and also in a re-interpretation of history; in fact his original ambition was to write a poetic history of the entire world, but that turned into a sort of series of works he called the Book of the Wild Rose. The Queen's Diadem is part of that set.
Almqvist sets his novel at the time of the assassination of King Gustav III in 1792, and many of his characters are real people, but the main characters are fictional. We have two sisters in love with two cavaliers who are involved in the assassination plot, and at the center--of everything--is the enigmatic Tintomara. Her names change--in fact she has no real name. Her clothing (therefore gender) changes--it is never clear whether she is a boy or a girl. She is beautiful and irresistibly alluring to everyone, and that throws her into despair.
It's all right in the Romantic tradition; there are mistaken identities, masquerades, duels, scheming dukes, and everything you could want, though it is not Gothic. There is a lot of symbolism, and the story is told using several different forms, shifting between novelistic narrative and dramatic dialogue. It has as many layers and baroque frames as an Isak Dinesen story (I think she must have been very influenced by Almqvist).
For some reason, The Queen's Diadem was not translated into English until 20 years ago or so. It's this fantastic novel, one of the greatest works in Swedish, but practically unknown in English. The assassination of King Gustav may, however, be familiar to opera fans; Verdi wrote Un ballo in maschera about it. The character of Tintomara has been very influential in Scandinavian art, and a film was made about her in 1970. (After poking around Youtube a bit, it seems that she also got her own opera, written by someone named Werle.)
If you're interested in European Romantic literature, put this on your list. It's really something.
A note, though--I'd forgotten that this book was really expensive for some reason. It's since been translated again as The Queen's Tiara, so be sure to look for it under both titles. The link I've provided goes to the newer edition.
Also--the book is absolutely littered with Swedish placenames, At all times, you could trace everyone's location on a map, so that could be a bit tricky for a reader not familiar with how they work. Happily there are lots of helpful footnotes, but the main thing is just to know that torget means a square, kyrkan is a church, and gatan is a street. The majority of placenames end with one of those three!