The hero, who like many Lagerlöf characters is given to doing rash, impulsive things, has a huge row with his girlfriend. He says he's going out, and he's going to propose to the first woman he meets. (In late 19th century Sweden, this made sense; today, I suppose he would have gone to an Internet mail-order bride site). The first woman who comes along is, indeed, incredibly unsuitable, but marries her anyway. Then he spends a good while wondering why the hell he did that. But, in the end, both to his and the reader's surprise, he finds he loves her after all.
A similar theme occurs in Jerusalem, which is generally considered the author's masterpiece. I've often wondered what she was saying here. She was deeply religious; if she'd been a lesser writer, I'd have discounted it as mealy-mouthed Christian propaganda about the sanctity of marriage, sort of a version of Stephenie Meyer syndrome. But Selma Lagerlöf was a genius, and I don't think that explanation fits well. I'm more inclined to read it as an interesting psychological observation. She's saying: guys, this happens sometimes, draw your own conclusions about why. Love's strange.
My (Swedish) wife, who knows Selma Lagerlöf much better than I do, says I've completely misrepresented this book! I suppose I ought to re-read it. Meanwhile, she could post a review of her own...
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