Saul Bellow, the Nobel laureate and self-proclaimed historian of society whose fictional heroes -- and whose scathing, unrelenting and darkly comic examination of their struggle for meaning -- gave new immediacy to the American novel in the second half of the 20th century, died yesterday at his home in Brookline, Mass. He was 89.

His death was announced by Walter Pozen, Mr. Bellow's lawyer and a longtime friend.

''I cannot exceed what I see,'' Mr. Bellow said. ''I am bound, in other words, as the historian is bound by the period he writes about, by the situation I live in.'' But his was a history of a particular and idiosyncratic sort.

The center of his fictional universe was Chicago, where he grew up and spent most of his life, and which he made into the first city of American letters. Many of his works are set there, and almost all of them have a Midwestern earthiness and brashness. Like their creator, Mr. Bellow's heroes were all head and all body both. They tended to be dreamers, questers or bookish intellectuals, but they lived in a lovingly depicted world of cranks, con men, fast-talking salesmen and wheeler-dealers.

In novels like ''The Adventures of Augie March,'' his breakthrough novel in 1953, ''Henderson the Rain King'' and ''Herzog,'' Mr. Bellow laid a path for old-fashioned, supersized characters and equally big themes and ideas. As the English novelist Malcolm Bradbury said, ''His fame, literary, intellectual, moral, lay with his big books,'' which were ''filled with their big, clever, flowing prose, and their big, more-than-lifesize heroes -- Augie Marches, Hendersons, Herzogs, Humboldts -- who fought the battle for courage, intelligence, selfhood and a sense of human grandeur in the postwar age of expansive, materialist, high-towered Chicago-style American capitalism.''

Mr. Bellow said that of all his characters Eugene Henderson, of ''Henderson the Rain King,'' a quixotic violinist and pig farmer who vainly sought a higher truth and a moral purpose in life, was the one most like himself, but there were also elements of the author in the put-upon, twice-divorced but ever-hopeful Moses Herzog and in wise but embattled older figures like Artur Sammler, of ''Mr. Sammler's Planet'' and Albert Corde, the dean in ''The Dean's December.'' They were all men trying to come to grips with what Corde called ''the big-scale insanities of the 20th century.''

At the same time, some of his novellas and stories were regarded as more finely wrought. V.S. Pritchett said, ''I enjoy Saul Bellow in his spreading carnivals and wonder at his energy, but I still think he is finer in his shorter works.'' Pritchett considered Mr. Bellow's 1947 book ''The Victim'' ''the best novel to come out of America -- or England -- for a decade'' and thought that ''Seize the Day,'' another shorter book, was ''a small gray masterpiece.''

All his work, long and short, was written in a distinctive, immediately recognizable style that blended high and low, colloquial and mandarin, wisecrack and aphorism, as in the introduction of the poet Humboldt at the beginning of ''Humboldt's Gift'': ''He was a wonderful talker, a hectic nonstop monologuist and improvisator, a champion detractor. To be loused up by Humboldt was really a kind of privilege. It was like being the subject of a two-nosed portrait by Picasso, or an eviscerated chicken by Soutine.''

Mr. Bellow stuck to an individualistic path, and steered clear of cliques, fads and schools of writing. He was frequently lumped together with Philip Roth and Bernard Malamud as a Jewish-American writer, but he rejected the label, saying he had no wish to be part of the ''Hart, Schaffner & Marx'' of American letters. In his younger days, he was loosely allied with the liberal and arty Partisan Review crowd, led by Philip Rahv and William Phillips, but he eventually broke with them saying, ''They want to cook their meals over Pater's hard gemlike flame and light their cigarettes at it.'' He spoke his own mind, without regard for political correctness or fashion, and was often involved, at least at a literary distance, in fierce debates with feminists, black writers, postmodernists.

On multiculturalism, he was once quoted as asking: ''Who is the Tolstoy of the Zulus? The Proust of the Papuans?'' The remark caused a furor and was taken as proof, he said, ''that I was at best insensitive and at worst an elitist, a chauvinist, a reactionary and a racist -- in a word, a monster.'' He later said the controversy was ''the result of a misunderstanding that occurred (they always do occur) during an interview.''

In his life as in his work, he was unpredictable. He was the most urban of writers and yet he spent much of his time at a farm in Vermont. He admired and befriended the Chicago machers -- the deal-makers and real-estate men -- and he dressed like one of them, in bespoke suits, Turnbull & Asser shirts and a Borsalino hat. He was a devoted, self-taught cook, as well as a gardener, a violinist and a sports fan.