Johnny Marciano is a New York Times bestselling author and illustrator. Most recently, he is the co-author of the ongoing Klawde series of illustrated chapter books with Emily Chenoweth. With Sophie Blackall, he is the co-creator of the Witches of Benevento series. He has published several standalone middle-grade novels, including The Nine Lives of Alexander Baddenfield and The No-Good Nine, and three books of nonfiction for adults: Anonyponymous: The Forgotten People Behind Everyday Words, Toponymity: An Atlas of Words, and Whatever Happened to the Metric System?: How America Kept Its Feet. His latest project, the picture book How Did Humans Go Extinct?, was released in 2021 from Black Sheep/Akashic. As John Bemelmans Marciano, he has also authored and illustrated five Madeline books, continuing the series created by his grandfather, Ludwig Bemelmans. He lives in New Jersey with his wife and daughter.