Since the publication of his first novel, Peter Nimble and His Fantastic Eyes, starring a blind 10-year-old orphan who is a skilled thief, Pittsburgh-based author Jonathan Auxier has been crafting magic-infused and adventurous middle-grade novels that have earned accolades and landed on bestseller lists. In his new work, Sweep: The Story of a Girl and Her Monster, Auxier introduces a fierce girl coming of age in the bleak world of Victorian London chimney sweeps, where she finds salvation in her friendship with and care for a magical monster. We spoke with Auxier about this long-gestating project, and what it was like to research the history of the brave, little-known child laborers called “climbers.”

How would you booktalk Sweep to an audience of young readers?

Sweep is the story of a girl and her monster and it’s set in the world of chimney sweeps. If you are like me, or most people, when you think about chimney sweeps you think of them as jolly guys dancing on rooftops like from Mary Poppins. But the reality is that that is a lie. For hundreds of years, chimney sweeps were not these happy, jolly people.

Even though fireplaces are big, the chimneys are very small and adults can’t fit up inside them to clean. They hadn’t developed brushes to do it, so they had to use children—the smaller the better. The chimney sweeps would hire these kids, they would sometimes purchase them from their parents or even kidnap them, and send these kids called climbers up and down scrubbing out chimneys all day long, and it was brutal and dangerous work. It’s recorded as one of the most dangerous jobs in history and it was happening to children and it was happening in our own homes.

Enter Nan Sparrow. Nan is 11 years old and she is tough and smart and might be the best climber who has ever lived. She’s also very, very lucky. She’s beaten the odds again and again and has survived this long and is just about to graduate and become an official apprentice. But before that can happen, she finds herself stuck in a chimney. Not just any chimney—she’s wedged in tight in a chimney that is actually on fire. She realizes she is trapped and there’s no way out, and she ends up screaming for help and blacking out. When she wakes up she discovers, first, that she’s somehow miraculously alive. She’s in an old abandoned attic, and she’s not alone, because there, huddled in the corner is this creature, unlike anything she’s ever seen. Its body is dark and crumbling, actually made from ash and soot. It was born inside that burning fireplace. This creature is called a golem, his name is Charlie, and he becomes Nan’s friend. So, this is the story of how Nan and Charlie save one another and then go out and save other kids who are just like her.

What was the initial spark to create Nan’s story?

Probably the first spark came from my wife. A lot of my ideas come from her. She has a Ph.D. in Victorian children’s literature and she’s always passing me things that come from her research that she finds, historical facts. She knows that if it’s really horrifying and disturbing, I’m going to be very excited about it.

Years ago she handed me a book called The Water-Babies by Charles Kingsley. A lot of people have heard of The Water-Babies, it’s considered kind of the antecedent to Alice’s Adventures in Wonderland, but not as many people have read it. I did, and the book is insane! The first 50 pages are amazing, and it’s what excited me, because it introduced me to this world of chimney sweeps and climbing boys, the kids who work for chimney sweeps. I’d never really known about that history and I’d never known just how awful it is. And pretty much the second I started reading about it, the character of Nan Sparrow emerged, fully formed.

I was really interested in a girl who somehow had been able to survive in a life like this, but in order to do that, she had had to close all the childlike parts of herself off. I wanted a kid that was tough and resilient, but who was also in need of a chance to ignite her sense of wonder again. The whole story built from that. I thought, what if she found a monster and had to raise it like a child, or like a friend and teach it about the world? Would she choose to teach it that the world was horrible? Because her world was pretty bad. Or would she choose to teach it that the world was wondrous?

In the book, Nan’s monster is further defined as a golem. What’s the significance of the golem in your story?

The golem is named Charlie and Charlie’s story took a parallel track that actually started before the chimney sweep stuff. I’ve known about golems for a lot of my life. They make appearances often as sort of minor monsters in fantasy literature. You see them a lot in board games and video games these days. They’re always these mindless hulking beasts made from rock or sometimes steel or iron, and they have an identity as big, mindless guards.

When I was 19, my father was teaching in Prague and I went with him for a couple of days, the only time I’ve taken a trip abroad. When I got to Prague, I discovered that that city is the birthplace of the great golem story [“The Golem of Prague”], and it’s very closely tied to the city’s history. The golem there was tied closely to Judaism and not only that but a history of persecution. The golem is not just a generic protector, but it’s protecting people who are in serious need, people who are being persecuted. I thought there was beauty to the idea that it was a story and a character born out of the fact that the city of Prague was persecuting its Jewish citizens, and then hundreds of years later it had become a celebrated image for the whole city. There’s something beautiful about that, and a little bit sad, especially in light of the fact that in almost all the golem stories you find, even when the golem does its job and manages to protect the person who creates it, the golem’s ending is not always happy. So you have this beautiful heroic creature who is also destined to be a little bit tragic. That really drew me in.

For years after that I was always thinking about golem stories and I actually had a game I would play where I would draw in my journals and sketchbooks golems made from different things: a golem made from shards of glass, or Skittles, or even one time, ash and hardened soot. Several years later, when I had this chimney sweep story and I needed something magic to happen to this hero, Nan Sparrow, I thought, what if she found this creature and it was a golem or she thought it was a golem, and it was born inside the same sort of crucible that had formed her, inside a chimney?

The book seems to be about finding a family when you need it most and the intense love of being a parent. Is there a connection to these themes in your own life?

One of the connections or ideas in the book is certainly that your family is something that you choose. And those relationships are much more meaningful than the biological ones. That’s something that I think is pretty universal for anyone who’s lived long enough. Because invariably the people that we think are going to be the most supportive are occasionally going to falter or not come through for us, and we’re going to discover people who aren’t blood relations who do come through for us, and support us and understand us in a way. That’s what deep friendships are; it’s really just an act of family-making. I think that’s something a lot of kids are feeling at [Nan’s] age, and that feeling doesn’t go away.

In terms of a deeper biographical connection, one of the core elements of Sweep is the idea that part of the reason Nan is so good at her job and she’s been able to survive is because for her earliest years she was raised by a man who is simply referred to as “the Sweep.” Even though most chimney sweeps were really horrible, this man was wonderful and caring and taught her how to do the work, but also how to carry the burden lightly, and was just sort of this enchanting person. And then when she was six years old, she woke up one morning to discover that the Sweep was gone. One day, I wrote what ended up being the first chapter of the book, which talks about these early years and the moment when the girl wakes up to discover she’s alone. And at that point in my life, this was close to 10 years ago, I put the book down because I knew that I was not mature enough as a writer or even a human being to really tell the story that I seemed to be setting up. I knew that at some point I would have my own kids and I would understand what it might feel like to be tied to a person that you can’t help but protect.

And lo and behold I had kids, a bunch of them, in succession and most crucially, our third child was the sort of baby who was not really built to thrive. She had a serious congenital heart defect, and we spent the first couple years of her life very, very frightened for her. Jumping ahead she’s a healthy and happy two-year-old right now and everything is good. But going through that experience of loving someone so much you might not be able to protect was driving me crazy, but it also was sort of conditioning me to understand how to write this book. I don’t think I could have written the book without going through that experience, and conversely I don’t think I could have gone through that experience without writing the book.

You’ve mentioned that this book took a very long time to write, and as you noted, you set it aside for a number of years. How did this creative journey compare to the writing of your other books?

I should preface this by saying that I’m an extremely slow writer. I’m a fast typist, but I throw away a lot. It’s pretty typical for me to write 10 pages in a day and literally just delete them at the end of the day because they weren’t right. A lot of my books have taken in the neighborhood of seven or eight years. But I’m coming back to them again and again, or jumping between things because it takes me a long time to figure out what I’m really wanting to say. Often the other books take so long because I’m trying to “brute-force” the problem.

The one difference with Sweep was that—and I’m grateful for this—as soon as I wrote that first chapter, I had a very clear sense that I just wasn’t up to the challenge yet. It was unique in the sense of really putting it away for several years. And luckily I had other books to keep me busy and kids to keep me busy. When it finally came time to sit down and write Sweep for real, aggressively all day, every day, I’d been thinking about it for years and years. But even so, it took about three solid years of constant writing to actually find the story.

It must feel really good to have this one done!

It does. There’s a lot of romance around people taking a long time on projects and I think that’s all garbage. I wish I were faster.

What kind of research did you do for the book?

If we think about that gap between putting the story in a drawer and being ready to write it, I was filling that time pretty consistently with some heavy research on Victorian London. One of the difficulties of this book is it spans all social strata, so I needed to understand what the poorest of the poor were like, but I also needed to understand what the homes of the wealthiest were like. I needed to know the streets very well. I needed to know the slang of multiple different cultures, the state of the Jewish population in London at this time, and the state of labor laws in London at this time. That really did take several years for me to wrap my head around.

For me some of the best tools that were most helpful were titles by Judith Flanders (The Victorian City: Everyday Life in Dickens’ London). I read lots of other books about Victorian London, but she really drills deep and understands how to communicate what it would feel like to live there. The other two biggest resources: one was social activist and journalist Charles Booth who toward the end of the century created these extremely famous poverty maps. They were huge, enormously detailed maps of London where he was also highlighting the average income of every single person in the city through color coding. And, much like the FBI agent tracking the serial killer in a movie, I had this huge board with the map on it, with threads and sticky notes tracking Nan’s movements. That map became a powerful tool for visualizing the city seeing just how close wealth was to extreme poverty. Another resource from the 19th century was Henry Mayhew’s seminal book London Labour and the London Poor. He was one of the first journalists in history to actually go into the most impoverished parts of London and record these peoples’ lives.

And I will be totally honest—because it was gigantically helpful—for all my research about architecture and things like that, the most valuable resource was the Assassin’s Creed video game that was set in London [Assassin’s Creed Syndicate]. I had an enormously difficult time understanding the structure and shape of rooftops in London at that time, which is extra hard to do because it was bombed into oblivion in the Second World War. But in that game, your character can run along these rooftops that have been gorgeously and painstakingly reconstructed from research. This was actually a tip I got from fellow writer Lou Anders, and his advice is if you are writing a historical novel the first thing you should do is to see if there is a big-budget video game set in that age, because that means they spent literally a million dollars recreating an environment that you can then walk around in. It was the most delightful form of “research” that you can imagine.

What’s the takeaway that you hope readers find in Sweep?

I was really discovering a lot about what it means to care for someone while writing the book, in my own life, and in the story. And the central idea in the book that emerges is this idea that we save ourselves by saving others. If there’s anything that I’m hoping readers take away from the story it’s that.

Sweep: The Story of a Girl and Her Monster by Jonathan Auxier. Abrams, $18.99 Sept. 25 ISBN 978-1-4197-3140-2