Reaching into her childhood memories of the Swedish countryside, Lindgren wrote more than 100 works, including novels, short stories, plays, song books and poetry. Generations of children around the world have grown up with the characters created by Lindgren - the red-haired Pippi Longstocking, the mischievous Emil and Ronia the Robber's Daughter.
Lindgren died in her sleep at her Stockholm home after several days of illness, said Lennart Frick, the husband of Lindgren's longtime secretary.
"Astrid maintained her personality until the end," her friend, Margareta Stroemstedt, told the newspaper Expressen, adding that Lindgren spent her final days surrounded by family members.
Lindgren wrote some 30 books and several plays, many of which have been made into films, television series, radio shows and cartoons. Her books have sold over 100 million copies in 55 langauges.
She was awarded dozens of Swedish and international prizes for her books, among them the Hans Christian Andersen medal in 1958, which is considered the ultimate accolade for an author of children's books.
Lindgren wrote about what she later called her own happy childhood in stories about the Noisy Village, where children romped through green forests in summer, skated on a frozen lake in winter and went fishing for crayfish in the fall.
Her most popular character was Pippi Longstocking, which was an instant hit among children when she first appeared in 1945. But parents often were shocked by the unruly Pippi, who rebelled against society and happily mocked institutions like the police and charity ladies.
Another favorite figure was Karlsson-On-the-Roof, who described himself as "handsome, remarkably wise, and just plump enough in fact a Man in his Prime." With a propeller on his back, he flew from his home on an apartment rooftop in central Stockholm.
"I write to amuse the child within me and can only hope that other children may have some fun that way too," Lindgren once wrote.
Though Lindgren excelled in playful storytelling, she didn't avoid difficult matters. She wrote about evil, death and fear in a straightforward but tender way. She taught her readers, child or adult, that you can be brave even if you're scared.
That is the theme in some of her most beloved classic novels, like the 1954 "Mio, My Son," in which a fatherless and lonely boy fights evil in the mysterious Land Far Away, and the 1973 "The Brothers Lionheart," in which young Rusky proves himself just as courageous as his elder bother.
Lindgren was born Astrid Ericsson on Nov. 14, 1907, the daughter of a farmer in Smaaland, a hilly wooded province in southern Sweden.
Unwed and pregnant at age 19, she left her shocked community in Vimmerby for the capital, Stockholm, where she had a son, went to secretary school and got a job in an office. ive years later she married Sture Lindgren and in 1934 the couple had a daughter, Karin, who was the real inventor of Pippi Longstocking.
"Karin was ill and asked me to tell her a fairy-tale. I asked her what about, and she said `about Pippi Longstocking.' So I did," Lindgren later wrote.
Right there and then Lindgren made up a tale of the strongest girl in the world who feared nothing and no one, had a bag full of gold coins and carried a monkey called Mr. Nilsson on her shoulder.
It wasn't until Lindgren was bedridden with a badly twisted ankle that she decided to put the stories on paper and give them to her daughter. She sent the manuscript to a publisher, who turned it down. But by then she had rediscovered the joy of writing.
Her first book was published in 1944, a story for teen-age girls called "Britt-Mari Opens Her Heart." It won second place in a literature competition sponsored by the publisher. Pippi Longstocking took first prize the next year.
Pippi was full of magic and make-believe, while other books like those about her own favorite character, the mischievous farmer boy Emil (published in 1963, 1966, 1970, 1986) were stories about growing up in the Swedish countryside and the wonders of childhood.
Lindgren was immensely popular in her home country. Few Swedes will ever forget her restful voice reading the stories that have become an integrated part of Swedish culture and collective consciousness. A theme park, displaying several of the settings from her books, opened in 1989 in her hometown, and attracts about 300,000 visitors yearly.
At times, Lindgren voiced political concerns. In 1976 she received a tax demand that outstripped her income, and criticized tax legislation in the fierce satire "Pomperipossa In the World Of Money." The law was changed.
She defended children's rights and animal welfare, lobbying an animal rights bill into law in 1998. That year the Astrid Lindgren's Children's Hospital opened, one of the biggest children hospitals in northern Europe.
She submitted her last manuscript, a short mystery story, in 1987. Her eyesight and hearing deteriorated and she began to find writing "a huge assignment." She spent her last years in the modest apartment in Stockholm where she had lived all her adult life.
Lindgren was widowed in 1952, and her only son, Lars, died in 1986. She is survived by her daughter and several grandchildren and great-grandchildren.
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