Pulitzer Prize-winning novelist A.B. Guthrie Jr., whose mountain men and settlers showed both the grandeur and the grimness of the Old West, died Friday. He was 90.

The death was announced by the family, who said funeral arrangements were pending.Guthrie had been in poor health for several months and had been in hospitals in Choteau and Great Falls. He spent his final days at his ranch on the Rocky Mountain Front near Choteau.

Guthrie was famed chiefly for six historical novels that gave a lusty but unromanticized look at the settling of the American West from 1830 to World War II.

The most famous, "The Big Sky," launched his career in 1947, and "The Way West," published in 1949, won the Pulitzer Prize for fiction in 1950.

"These Thousand Hills" followed in 1956, and the three are considered Guthrie's finest works.

All three were made into movies that Guthrie disliked, but he wrote the screenplays for two successful movies, "Shane" in 1953 and "The Kentuckian" in 1955.

His other historical novels were "Arfive," which won the 1970 Western Heritage Wrangler Award; "The Last Valley," 1975, and "Fair Land, Fair Land," 1982.

Guthrie also wrote short stories, essays and mystery novels with a Western setting, the latest being "Murder in the Cotswolds" in 1989. His first novel, in fact, was a 1943 cow-country whodunit titled "Murders at Moon Dance," but he considered it so bad that he refused to discuss it and often called it "trash."

The love of the landscape that drove Guthrie to write about the West also made him an unabashed environmentalist who warned that "progress" sometimes isn't.