James Michener, the prolific and massively popular author who established a new form of historical fiction with epics such as Hawaii, Centennial and The Source, died Thursday at his home in Austin, Texas. He was 90.

Michener’s death came four days after it was announced that he had declined further dialysis treatment for the kidney failure that struck him in 1993, “Do you know how easy it would be to commit suicide?” Michener told a reporter last year. “Just not keep an appointment.”

By all accounts, it was the first time in a long and eventful life that Michener’s characteristic optimism failed him. Born an orphan, raised in poverty, he rose to become a Pulitzer Prize-winning author for his first novel, 1947’s Tales of the South Pacific.

Michener hit upon a winning formula with Hawaii in 1959, combining deep research in the history and geography of a specific place with fictional stories spanning decades, centuries, sometimes millennia. Thereafter he wrote a succession of best-selling historical epics that endeared him to millions of readers around the world, but alienated critics.

His was one of the remarkable literary careers of the 20th century. His fame is based on more than literary talent: His life embodied values that Americans like to see in themselves. He was smart, hardworking and lucky. There is no doubt his books will continue to be read, if only for the plucky, down-to-earth humanism that pervades his novels.

Michener was also a major art collector and prodigious philanthropist, living modestly and giving away more than 90 percent of his wealth _ approximately $120 million _ mostly to universities and art museums. He was listed as one of the top 25 most generous Americans by Forbes magazine, which estimated he gave away $24 million last year alone.

The $1 million he donated to the University of Miami after researching his novel Caribbean there in the late 1980s enabled the establishment of a graduate writing program.

“He is someone I will genuinely miss,” said poet John Balaban, director of the creative writing program at U.M. “He was unique, like Allen Ginsberg, though for very different reasons. We won’t see another one like him.”

Michener’s own story rivals anything in his books, and in fact, forms the basis of his second novel, The Fires of Spring.

Born on Feb. 3, 1907 in Bucks County, Pa., Michener was raised first in an orphanage and then by working-class adoptive parents Edwin and Mabel Michener. The hardships of his childhood made him a lifelong liberal and advocate for the poor. A Quaker, he earned a scholarship to Swarthmore College, where he graduated with a degree in English in 1929.

“I am pre-eminently a child of the American education system, which tries to identify and isolate people like me and give them awards and scholarships,” Michener told the Sun-Sentinel in 1988. “After age 14, life was easy for me. I received one scholarship after another.”

From 1933 to 1941, Michener taught English at various schools including Harvard, taking time out to earn a master’s degree. He worked as an editor at Macmillan publishing company in New York from 1941 until his enlistment in the Navy the following year.

Michener based his first novel on his experiences in World War II, winning the Pulitzer for Tales of the South Pacific. He was a late-blooming writer, making his debut at age 40.

“He was an idealistic guy who believed in people and wanted to see the good in everyone _ and did,” said Lester Goran, novelist, short-story writer and U.M. professor. “Tales of the South Pacific was an enormously promising novel with a sort of artistic impulse that gained a sense of what the war and the people were like.”

It was not, however, a popular novel _ until Rodgers and Hammerstein adapted it into a hit musical. Critics admired much of Michener’s early work, which includes The Bridges at Toko-ri and Sayonara, drawn from the Korean War, and a nonfiction book about the 1956 Hungarian revolt, The Bridge at Andau.

The massive Hawaii was well-received in 1959, but when it became apparent that Michener had settled into a pattern of fictionalized histories, his literary reputation quickly declined.

“He told me once that if he had confined his books to one place, like Balzac and Paris,” said Goran, “that he might have been taken more seriously as a writer.”

Instead, Michener ceased to be a serious writer at all, at least in the literary sense, and became something else _ an industry. His typewriter was a factory upon which, with two fingers pecking, he processed facts into best-selling novels that also could be used as doorstops and further processed into movies _ or better yet, TV miniseries.

But readers loved these books, making best sellers of every historical opus he wrote _ including Caravans, The Source, Iberia, Centennial, Chesapeake, Poland _ until his last major commercial success, Texas, which, published in 1985, marked Michener’s decline, though he continued to work and publish to the end.

In 1988, Michener explained to the Sun-Sentinel how his incredibly popular historical epics had evolved. It was accidental, he said.

“I had lived in all the places in Hawaii,” Michener said. “Northern Japan, the South Pacific, Hawaii itself, even China for a brief period. I was probably the only person in the world who could have written that book at that time. I love exposition. If you are going to deal with those characters, you are obligated to look into their backgrounds. The reception to the book was favorable, and the others came in a natural sequence.”

Fourteen of Michener’s books have been adapted to other formats _ movies, plays or television, including a 26-hour miniseries based on Centennial. “My attitude is to get it written, put it on the shelf and let others worry about it,” he said. Only three productions pleased him, however _ South Pacific, The Bridges at Toko-Ri and Sayonara.

Michener conceded that his books are sometimes heavy going.

Michener once said that his books were read by people who read nothing else. Balaban told of an afternoon on a fishing boat with former U.M. dean Ross Murtin following a morning spent chatting with Michener.

“The charter boat captain came down and asked if we were talking about James A. Michener the writer,” Balaban said. “He had read everyone of Michener’s books and could discuss them far more knowledgably than we could.”

Appraising his achievements modestly, Michener regarded his critics with equanimity. Michener never complained, not even at the end. His only request on Monday, was for privacy. Whatever Michener’s eventual literary standing, he is an enduring a symbol of 20th century America at its best.