His daughter Aria Ungerer confirmed the death and said the precise date and cause were not known.
“He was in absolutely brilliant form in the past few days,” she said, and was writing a collection of short stories “about his alter ego, Mr. Malparti.”
Working primarily as a satirist, Mr. Ungerer published more than 140 books in German, French and English, including works of children’s literature and a collection titled “Guardian Angels of Hell” (1986), featuring interviews with sex workers at a Hamburg bordello. He was also a sculptor, printmaker, painter, caricaturist and antique toy collector, an ad man for the Ice Capades and a onetime food editor for Playboy magazine.
For the New York State Lottery in the late 1960s, he used a slogan, “Expect the Unexpected,” that echoed a saying by the Greek philosopher Heraclitus and was later used by the Village Voice newspaper. For the German city of Karlsruhe, four decades later, he designed a kindergarten in the shape of a white cat, with a whiskered nose, windows for eyes, a door for a mouth and a slide for a tail.
“No one, I dare say, no one was as original,” his friend Maurice Sendak, author of “Where the Wild Things Are,” told the New York Times in 2008. “Tomi influenced everybody.”
Raised in the Alsace region of France, Mr. Ungerer lived under Nazi occupation and hitchhiked across Europe before moving to New York City in 1956. He found work as an illustrator for publications including the New York Times, Life and Harper’s Bazaar, while creating posters for movies such as Stanley Kubrick’s “Dr. Strangelove” (1964) and briefly sharing an apartment with novelist Philip Roth.
But he became best known for his children’s books, including the illustrations for Jeff Brown’s 1964 classic, “Flat Stanley,” about a boy who is crushed flat by a bulletin board, slips inside envelopes to travel by mail, and restores himself to proper size with the aid of a bicycle pump.
Writing about outcast characters such as Emile the octopus and Crictor the boa constrictor, he received the Hans Christian Andersen Award, one of the highest honors in children’s literature, in 1998. A biography prepared for the prize described Mr. Ungerer’s picture books as “simple, wry and grotesque,” adding: “You can go exploring in his pictures, bursting with color, with surprising details, silhouette effects, soft yet precise outlines, and changing, plastic forms.”
Among his most celebrated works were “The Three Robbers” (1961), a moody, blue-hued tale of highway bandits who terrorize the countryside, and “Moon Man” (1966), in which the title character falls to Earth, enjoys its flowering landscapes, and is promptly thrown in prison, only to slip through the bars as he grows smaller as part of the lunar cycle.
While writing the children’s books that made him famous, Mr. Ungerer began working on erotic art and designing political posters, including pieces that protested segregation and the Vietnam War. One 1967 image, titled “Eat,” showed a disembodied hand force-feeding the Statue of Liberty to a yellow-skinned man; another, “Choice Not Chance,” showed a pilot decorating the nose of his plane with images of crying children.
Mr. Ungerer’s social life included poker games with the Cuban representative to the United Nations, and his political views seemed to catch the attention of federal investigators, particularly after he requested (and was denied) a permit to visit China.
In interviews, he often recalled being picked up by three FBI agents — or perhaps they were part of some other federal agency; he was never quite sure — and taken in for questioning after returning from a trip to France in 1960. He said they later tapped his phone and opened his mail.
For the most part, however, his political work was eclipsed by his erotic drawings, particularly those in “Fornicon,” a self-published 1969 book that Times journalist Randy Kennedy described as “a nightmare vision of mechanized pleasure.”
When Mr. Ungerer appeared at an American Library Association conference that year, according to one account in the New Yorker, he was inundated with questions from angry librarians, who asked how an illustrator of whimsical children’s books could also depict graphic sex acts. Recalling the incident, Mr. Ungerer said he replied with an expletive, saying, “If people didn’t [have sex], you wouldn’t have any children, and without children, you would be out of work.”
He was then effectively blacklisted in the United States, with many of his books removed from libraries and lost to American readers until about a decade ago, when Phaidon Press began reissuing his work. In Europe, his popularity soared; he sold millions of books in Germany and France. In 2007, a museum dedicated to his life and work opened in Strasbourg, France. The Council of Europe named him ambassador for childhood and education that same year.
He had, he told the Times, always espoused a belief that children had to be “respected” and more or less treated as adults.
“They understand the world, in their way. They understand adult language,” he said. “There should not be a limit of vocabulary. In ‘The Three Robbers’ I don’t use the word ‘gun.’ I say ‘blunderbuss.’ My goodness, isn’t it more poetic?”
The youngest of four children, Jean-Thomas Ungerer was born in Strasbourg on Nov. 28, 1931. His father was an artist, engineer and designer of astronomical clocks who died when Tomi was 3; his mother moved the family to Logelbach, near the Alsatian city of Colmar. During the war years, he said, he was forced to join the Hitler Youth and dig trenches for the German army, and he filled his notebooks with battlefield scenes.
Mr. Ungerer failed his high school graduation exams — his headmaster was said to have described him in a school report as a “willfully perverse and subversive individualist” — and subsequently traveled to northern Finland. He served with the French camel cavalry in Algeria and slowly made his way to New York, with $60 in his pocket and a “trunk full of drawings and manuscripts.”
A meeting with editor Ursula Nordstrom, of what was then Harper & Brothers, led to his first children’s book, “The Mellops Go Flying” (1957), about a family of acrobatic French pigs. The book became a hit and spawned several sequels.
Mr. Ungerer moved to Nova Scotia after his spat with the librarians and settled in Ireland in 1976. His later books included “The Joy of Frogs” (1985), a comic sex manual for amphibians, and children’s tales such as “Otto: The Autobiography of a Teddy Bear” (1999), about a stuffed bear in 1930s Germany.
His first two marriages ended in divorce. In 1971, he married Yvonne Wright. In addition to his wife, survivors include a daughter, Phoebe Ungerer, from an earlier marriage to Miriam Lancaster; three children from his third marriage, Aria Ungerer, Pascal Ungerer and Lukas Ungerer; a sister; and two grandchildren.
Mr. Ungerer was the subject of a 2012 documentary, “Far Out Isn’t Far Enough,” that took its title from a 1983 illustrated memoir about his years in Canada. The phrase, he said, referred to an artistic desire — even a necessity — to push ever further into the unknown.
“That’s what’s really fantastic about death; that’s why death has to be welcomed,” he said in a film clip published to his Twitter account after he died. “And when I die, I’ll find out what’s behind the far out. Maybe there’s nothing, but nothing is fantastic, too. Because if you’re faced with nothing, you can fill it up with your mind.”
Correction: An earlier version of this obituary reported that in the late 1960s, Tomi Ungerer devised the slogan “Expect the Unexpected.” Mr. Ungerer said he created and popularized the slogan, but it had previously been used by the Experiment in International Living, a study abroad program. The story has been revised.
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