Maurice Sendak, an author and illustrator whose dozens of works, notably “Where the Wild Things Are,” transformed children’s literature from a gentle playscape into a medium to address the psychological intensity of growing up, died May 8 at a hospital in Danbury, Conn., after a recent stroke. He was 83.

Starting in the early 1960s, Mr. Sendak introduced a dark, often powerfully surreal vision to a literary genre long dominated by precious and precocious tots. His books jettisoned the notion of warm and fuzzy bedtime stories in favor of the stuff of nightmares — monsters, abduction, even cannibalism.

Sendak characters could be rebellious and downright unpleasant, but in refusing to condescend or act as a balm, his books were also exceedingly popular with young readers for generations. The books showed that even children, confronting a range of often terrifying emotions, could through courage and resourcefulness begin to make sense of the world around them.

In underscoring those emotions and how young people react to them, Mr. Sendak became one of the most critically revered and entrancing writers of his era. The death was confirmed by Sandee Roston, executive director of publicity for HarperCollins Children’s Books. Mr. Sendak lived in Ridgefield, Conn.

The Sendak trilogy of “Where the Wild Things Are” (1963), “In the Night Kitchen” (1970) and “Outside Over There” (1981) “crashed open the gates” for what themes authors could address in children's literature, said Cathryn M. Mercier, director of the Center for the Study of Children's Literature at Simmons College in Boston.

Mr. Sendak was shaped foremost by a sickly and homebound childhood in Depression-era Brooklyn, the deaths of family members in the Holocaust and vivid memories as a youngster reading about the kidnapping and murder of aviator Charles Lindbergh's infant son.

An admitted obsession with “children and their survival” and the “humongous heroism of children” fueled a career of groundbreaking darkness in children's literature. President Bill Clinton presented him with the National Medal of Arts in 1996, saying, “His books have helped children to explore and resolve their feelings of anger, boredom, fear, frustration and jealousy.”

Mr. Sendak's illustrations were instantly recognizable, 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 pen-and-ink drawings and watercolors — with their echoes of William Blake and Henri Matisse, among others — became the subject of numerous exhibitions.

Mr. Sendak illustrated more than 100 books, more than a dozen of which he also wrote. They were translated into dozens of languages, sold millions of copies and won almost every top honor in his profession, from the Caldecott Medal to the Hans Christian Andersen Award.

In addition, Mr. Sendak worked in film, television and opera. In the early 2000s, he collaborated with Pulitzer Prize-winning playwright Tony Kushner on a restaging and book adaptation of Hans Krasa's children's opera “Brundibar,” which had been associated with being performed by children imprisoned at a Nazi concentration camp.

“The Holocaust has run like a river of blood through all my books,” Mr. Sendak once said, explaining that as the child of Jewish immigrants from Poland, the Nazi death camps were never far from his mind.

Mr. Sendak's greatest achievement was to elevate the picture book “to an individual, contained art form that integrates words and illustration,” Mercier said.

“Where the Wild Things Are,” considered an instant classic upon its publication, was an early inspiration for Mary GrandPre, who illustrated the dark “Harry Potter” books about a boy wizard.

The Sendak story was about the nighttime romp of a youngster, Max, who has been ordered to bed without supper. He imagines from his bedroom a fantastical journey to a land of large and grotesque beasts who crown him their king.

Max conjures the wild things as a way to channel his anger at being punished. When his frustration burns out after a “wild rumpus,” he returns to his house — and a warm meal.

Mickey of “In the Night Kitchen” is awakened by a strange thumping in a kitchen, and he meets oversize bakers who resemble the film comedian Oliver Hardy. The book's full-frontal nudity of the protagonist was considered shocking at the time, and librarians chose to draw diapers over the offending scene. “In the Night Kitchen” was a frequent target of censorship panels that removed it from public schools and libraries, according to the American Library Association.

Mr. Sendak told the Pittsburgh Post-Gazette in 2001 that reaction to the book worried him because “kids are just learning about their bodies and adjusting to their bodies. By banning the book or covering him with a little jock strappy thing only tells the kids that there is something wrong with the most natural thing in the world, your own human body.”

“Outside Over There,” about a girl named Ida who tries to rescue an infant sister who has been stolen by goblins, was based on the Lindbergh kidnapping.

Together, Max, Mickey and Ida represent the fearful idea that parents are unaware of the crises their children face, Mr. Sendak told the Times of London. “It happens right before your eyes as a parent,” he said, referring to those moments when children must fend for themselves. “You know that, and you don't see it. And that's the point that just totally fascinates me. Something colossal has just brushed by that's going to change a child's life and you might have helped — if you'd looked!”

Maurice Bernard Sendak was born June 10, 1928, in Brooklyn. His father, a dressmaker in New York's garment district, stimulated his imagination with tales spun from Jewish folklore. As a child, Maurice developed measles, pneumonia and scarlet fever, and his parents kept him inside for much of his childhood.

To adapt to his sheltered upbringing, he drew and concocted stories based on what he saw from his window. He also enjoyed seeing cartoons in theaters and called Mickey Mouse “an early best friend.” He named the main character from “In the Night Kitchen” after the Disney character.

Mr. Sendak was a lackluster student but excelled in art class. As a way to pass physics, he agreed to illustrate a textbook, “Atomics for the Millions,” written by his teacher. The assignment resulted in his illustrations being published for the first time, with a New York Times reviewer in 1947 praising the “splendid drawings” for their ability to “not only explain the material dealt with in the text but also lend a touch of humor to an otherwise completely sober discussion.”

Through a job dressing windows at toy store FAO Schwarz, Mr. Sendak met Harper & Row children's book editor Ursula Nordstrom, who hired him as an illustrator. His breakout moment came in 1952 with his drawings for “A Hole Is to Dig,” a collection of whimsical definitions by author Ruth Krauss, who became a frequent collaborator. The book earned Mr. Sendak a reputation. as a promising illustrator and brought him an active freelance career. He left the toy store and became a full-time illustrator in Manhattan.

Throughout his career, Mr. Sendak mined his personal life for professional inspiration. In 1960, he published “The Sign on Rosie’s Door,” based on a little girl he watched from his window as a child and admired for her bravery despite a difficult home life. The story inspired a 1975 TV special, “Really Rosie,” with music by Carole King that also was the basis for an off-Broadway musical.

The jet-setting dog of “Higglety Pigglety Pop! Or, There Must Be More to Life” (1967), written after the author had suffered a heart attack and learned of his mother's cancer, was modeled after Mr. Sendak’s Sealyham terrier, Jennie, who had recently died.

Before his partner of more than 50 years, psychoanalyst Eugene Glynn, died in 2007, he began working on a story about an orphaned pig who throws himself a giant birthday party. When it came out last year, “Bumble-Ardy” was the first book Mr. Sendak had written and illustrated in 30 years. “I did Bumble-Ardy to save myself. I did not want to die with [Glynn],” Mr. Sendak told NPR.

He illustrated several Grimm fairy tales in “The Juniper Tree” (1973). One of them involving a changeling baby, “The Goblins,” gave Mr. Sendak the idea for “Outside Over There” and touched on his previous anxieties about the Lindbergh kidnapping.

He said the shock of seeing impoverished children in the plush locales of Los Angeles and Rio de Janeiro pushed him to allude to such themes as homelessness, poverty and the AIDS epidemic in illustrations for two Mother Goose rhymes in “We Are All in the Dumps With Jack and Guy” (1993).

Mr. Sendak, who said he worshiped Mozart, did the set and costume design for a Houston Grand Opera production of “The Magic Flute” in 1980. His further work in opera included an adaptation of “Where the Wild Things Are.”

Mr. Sendak never had children but instead owned many dogs.

“I'm not a good parent type,” he told Entertainment Weekly in 2003. “It's strange, I have the gift in books of comprehending how wild children are, how terrifying they can be. But in real life they're much too frightening. They're too vulnerable. And it scares me. How could you ever calm down with a kid?”