Historical Fiction; Young Adult Literature; Coming-of-Age
While there's plenty that's complex about this book—if nothing else, it asks some of the Big Questions in life—when it comes to genres, it falls into categories pretty nicely. It's historical fiction because a good chunk of it is set during World War II. This obviously isn't ancient history, but it's definitely long ago that it comes up in your history textbooks, so historical this book most certainly is. And since none of the characters are real, we're also hanging out in fiction land.
Pop quiz: What's do you get when you combine history and fiction? Answer: Historical fiction. Boo ya.
As for the young adult lit and coming-of-age genres, well, they go hand-in-hand. This book is centered on young people—even Geertrui is a teenager for a good portion of it—which is a tell-tale sign that you're on YA turf. Plus the language is pretty straightforward and the plot is pretty accessible—though there's plenty of history in this one, you definitely don't need a PhD (or a BA for that matter) to follow along.
Since the young people this story centers on (we're including Geertrui) navigate some tough issues—sexuality, infidelity, and war definitely fit the bill—and all mostly on their own, you'd be hard-pressed not to see them come of age in the process. Though Jacob's vacation is pretty short, he definitely comes into his own, especially when it comes to kissing who he wants to kiss, and the same can be said of Geertrui as she argues for Jacob's safety, tends to his wounds, and explores s-e-x with him.
The Big Questions in life are hard enough—luckily the genres are about as straightforward as they come in this book.