"Author of splendid nightmares" Maurice Sendak died Tuesday at age 83. The prolific writer and illustrator is "widely considered the most important children's book artist of the 20th century," says Margalit Fox at The New York Times. His stories, especially the classic Where the Wild Things Are, were among the first popular tales to truly acknowledge that children experience darkness, and then to reflect those shadows right back at them. At first, that notion drew plenty of criticism, but ultimately turned Sendak into one of the most celebrated children's authors in modern history. Here, writers remember his legacy: 

He'll always be remembered for Where the Wild Things Are
When the book was published in 1963, it was an instant classic — and instantly controversial. The story of young Max, a grumpy boy who lashes out at his mother, is sent to his room without supper, and is then magically transported to a menacing forest populated by grotesque creatures who want to eat him, was "a startling departure from the sweetness and innocence that ruled childhood literature," says Valerie J. Nelson at the Los Angeles Times. Libraries banned it, but the book won the Caldecott Medal, was considered for the Pulitzer Prize, and eventually sold more than 19 million copies.

He explored imagination's darkest corners
In several books — not just Wild Things — Sendak upended the tried-and-true storyline of well-behaved young heroes and heroines on staid and static adventures, tales that were always "tied up in the end in a neat, moralistic bow," says Fox. Instead, he "wrenched the picture book out of the safe, sanitized world of the nursery and plunged it into the dark, terrifying, and hauntingly beautiful recesses of the human psyche." Perhaps it was because Sendak truly knew pain. He grew up in Depression-era Brooklyn, suffered the loss of family members in the Holocaust, and was haunted by the kidnapping and murder of Charles Lindbergh's son, says Becky Krystal at The Washington Post. His work reflected the "psychological intensity of growing up." 

He portrayed children as they really are
In Sendak's books, kids can be nice or nasty, says Jeanne Sager at The Stir. "They can be greedy or graceful. They can be scared. They can be forced to think. They are real kids living in a world devoid of the purple cats and talking unicorns" that inhabit other children's books. Sendak took kids (and their parents) to "that place deep down inside them, beyond the giggles and scraped knees… where they think thoughts you cannot hear, fear things you cannot see." 

He drew in a way that was unsettlingly beautiful
Sendak's drawings were instantly recognizable, says Krystal, "whether of a mischievous child in a wolf costume who tames minotaurs in a wild kingdom (from Where the Wild Things Are) or of plump, red-nosed pastry chefs who fold children into their cake batter (In the Night Kitchen)." His trademark crosshatched, bulbous images were "at once lovely and dreadful," says Fox. "He was able to convey both the propulsive abandon and the pervasive melancholy of children's interior lives."

He was absolutely prolific
Sendak illustrated more than 100 books, and wrote more than a dozen. He won nearly every top honor in his profession. His most recent picture book, Bumble-Ardy, was published in September 2011, and another is scheduled to be published posthumously in February 2013. He also worked in film, television, and opera, collaborating with playwright Tony Kushner in the early 2000s to stage and adapt Hans Krasa's children's opera Brundibar, which was performed by children imprisoned at a Nazi concentration camp.

He was a prickly, loving, complicated man
Sendak, who was gay and had no children, was famously both ornery and warm. He told Vanity Fair last year: "A woman came up to me the other day and said, 'You're the kiddie-book man!' I wanted to kill her." Despite occasional grumpiness, Sendak was dearly fond of his young fans, and had a sense of humor about himself, as exhibited during a recent viral interview on Comedy Central's The Colbert Report. Speaking with NPR's Fresh Air last year, he faced his own mortality: "I have nothing but praise now, for my life. I'm not unhappy... Oh God, there are such beautiful things in the world, which I will have to leave when I die. But I'm ready, I'm ready, I'm ready."