The Devil's Arithmetic, by Jane Yolen (pub. 1988)
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I didn't read this until 2016 (28 years after it was first published). I think I first became aware of it because of a 1999 TV movie based on the book, though I don't think I was aware of that until sometime in the 2010s. (I still haven't seen the movie, but I'd definitely like to, someday.) The book is historical fiction, which I think does an excellent job of giving us a small glimpse of the Holocaust (which we must never forget), and making it personal.
It begins in the present, with a nearly thirteen-year-old girl named Hannah Stern, who's going with her parents and her younger brother, Aaron, to her grandparents' house in the Bronx, for Passover Seder. (Her family lives not too far away, in New Rochelle.) Hannah doesn't seem to particularly like her Grandpa Will, though she is fond of her Aunt Eva (Will's sister, who lives with Will and his wife Belle, and had helped raise their son, Hannah's father). Hannah also isn't particularly fond of all the remembering that's such a big part of Jewish holidays like Passover. But she participates, anyway (as she has no choice). At one point during the Seder, she's sent to symbolically open the door and look for the prophet Elijah. She doesn't see him, of course, but she does see someone walking toward the house...
And then, the house Hannah is in is no longer her Grandpa Will and Grandma Belle's. It isn't even in America, but rather Poland. And while it's pretty obvious to the reader, it seems to take Hannah awhile to realize she's not even in her own time, anymore. The only other person in the house is a woman named Gitl, who calls her "Chaya." (That's Hannah's Hebrew name, which she'd been given to honor a friend of Aunt Eva's who had died during World War II. And of course, that little nugget of info immediately made me wonder if Hannah would turn out to be the very person she was named after.) Anyway, the man she had seen coming toward the house was Shmuel, Gitl's brother. The two of them have been looking after "Chaya" (their niece) ever since her parents died of an illness that had nearly claimed Chaya's life, as well. (Of course this is all very confusing for Hannah, as is the fact that she suddenly understands Yiddish.) Chaya and her parents had lived in a city called Lublin, so I guess she isn't used to the way of life in the small shtetl where her Aunt Gitl and Uncle Shmuel live. (I don't think the town is ever named, but I may be mistaken.) So, her guardians account for the strange things Chaya says by some remaining effects of the fever she'd had, and by her being accustomed to life in Lublin. At first, Hannah tries to make them understand the truth, but she soon gives up. And after awhile, she begins to forget her life as Hannah (even if the book's narrative voice continues to call her by that name).
Shmuel is engaged to a woman named Fayge, from the nearby town of Viosk, so he and Gitl and Chaya and various other people from their shtetl journey there, for the wedding. Along the way, Chaya befriends a few girls her age. There's also a widower named Yitzchak, who is raising two young children, and who I guess might be interested in Gitl romantically, though she's not interested in him. (But none of that is really an important plot point.) What is somewhat important is that Hannah likes to tell stories, and she does so with her new friends (recounting movie plots, mostly; her friends are aware of movies, but have never seen any, and probably all the movies she talks about are from the future, not that her friends would know that).
Anyway, once everyone arrives at Viosk, before the wedding can even happen, Nazi soldiers force them into trucks and take them to a train station, where they're then herded into boxcars and transported to a concentration camp. The trip itself is horrible in a lot of ways, so that it's almost a relief to finally get off the train, in which they'd been packed like sardines and had to spend days just standing, as there was no room to sit. But of course, getting to the camp was really the beginning of the horrors they'd have to endure. The women and children all went to one section of the camp, separate from the men. And everyone was put to work; Chaya and her friends had to clean huge cooking pots. It was at that job that they made a new friend, a ten-year-old girl named Rivka, who was already a veteran of the camp. Almost her entire family had been killed, except her brother Wolfe, whom we don't see until near the end of the book. Rivka teaches them the rules of surviving in the camp. But of course, survival is never a certainty, as every day prisoners are "chosen" for "processing," which means being killed in the gas chambers. By now, Hannah doesn't remember her old life at all, though there are occasional flashes of remembrance of things that she no longer even understands the meaning of.
Well... the book is quite short, but there are a lot of details I don't want to get into. It's pretty horrible, but there's always at least a small measure of hope, even if that hope is only to survive, so that the story can be told. Interestingly, near the end, Chaya begins to remember more facts about Hannah's present, which itself becomes a story to tell her friends, to give them hope for the future (even while horrifying them with the unthinkable number of Jews who would ultimately be killed in camps like theirs). Of course, Hannah eventually finds herself back home with her real family, and shares a simple, but deeply moving conversation with her Aunt Eva (whose identity in relation to Chaya's experiences in the past is easy to guess, at this point). And... I think when Eva said what she used to be called, even though I already knew what that name would be, I think that might be the first time I actually cried, while reading the book. (I could be wrong about that, though, because there was plenty to cry about before that.) I think that moment, or that whole scene, hit me so hard because it represented a mix of a lot of powerful emotions, both good and bad. In any event, the book is simply amazing.