Ralph Stanley in 2006. (Steve Helber/AP)

Ralph Stanley, a masterful bluegrass singer and banjoist whose performances on the Grammy Award-winning movie soundtrack album “O Brother, Where Art Thou?” helped inspire a bluegrass resurgence in the 2000s, died June 23. He was 89.

He died at his home in Sandy Ridge, Va., because of difficulties from skin cancer, publicist Kirt Webster told the Associated Press.

Mr. Stanley, widely regarded as an eminence in bluegrass, helped launch the careers of such country and bluegrass stars as Larry Sparks, Ricky Skaggs and the late Keith Whitley.

In recent decades, Mr. Stanley won some of the highest honors in his profession — including a National Medal of Arts — and recorded with such performers as Bob Dylan, Emmylou Harris, George Jones, Lucinda Williams and Joan Baez. Jerry Garcia of the Grateful Dead once called him “the most perfect singer alive.”

It was a plaintive, nimble and haunting voice that blended elements of Primitive Baptist church choirs and the Grand Ole Opry, music on which Mr. Stanley was weaned in far southwestern Virginia.

Undated file photo of pioneer bluegrass musicians Ralph Stanley (with banjo) and his brother, Carter Stanley (with guitar). (file photo)

With his older brother Carter, Mr. Stanley rose to musical prominence in the 1950s as a member of the bluegrass band known as the Stanley Brothers and the Clinch Mountain Boys. They were immediately at the forefront of a bluegrass sound first popularized by Bill Monroe — with its gospel harmony, Celtic fiddling, and blues, pop and jazz influences — and the mutual rivalry and admiration between Monroe and the Stanley Brothers continued for years.

Dark-tinged and mournful Stanley Brothers recordings from the late 1940s and 1950s — “White Dove” and “The Fields Have Turned Brown,” both written by Carter Stanley, and “Rank Stranger” — tapped into the sorrows of rural people, many of whom had moved to the city.

Not all Stanley Brothers music was doleful. The rollicking “How Mountain Girls Can Love” and Mr. Stanley’s vibrant instrumental showcase “Hard Times” showed their up-tempo side.

How Far to Little Rock” (1960), a vaudeville routine set to an old fiddle tune, “Arkansas Traveler,” gave the Stanley Brothers their biggest country radio hit. In it, Mr. Stanley, as a city slicker lost in the country, questions and gets smart answers from Carter, portraying a wisecracking local yokel:

“Hello, stranger.”

“Well, hello, stranger.”

“Could you tell me how far it is to Little Rock?”

“Well, no sir, I couldn’t, buddy, but they’s a devil of a big ’un down here in South Coal Creek.”

Carter Stanley — hard-drinking, hard-charging, gregarious and extroverted — was the master of ceremonies onstage, while Ralph Stanley — the more reserved brother — handled business offstage. When Carter, at 41, died of cirrhosis in 1966, Mr. Stanley briefly considered retirement before returning as the group’s frontman.

“I was worried. I didn’t know if I could do it by myself,” he once recalled. “But boy, I got letters, 3,000 of ’em, and phone calls” in support.

Mr. Stanley led the Clinch Mountain Boys for the next five decades with other singers, such as Larry Sparks, Roy Lee Centers, Charlie Sizemore and Mr. Stanley’s son, Ralph Stanley II, in the tenor vocal slot originally held by Carter Stanley. Notable instrumentalists in the group included lead guitarist George Shuffler, whose intricate style of guitar, known as crosspicking, emulated the syncopation of the bluegrass banjo.

In 1970, Mr. Stanley hired two teenaged singers, Ricky Skaggs, a multi-instrumentalist adept at mandolin, fiddle and guitar, and Keith Whitley, a singer who closely modeled his style on Carter Stanley’s. When Mr. Stanley arrived late for a gig after a flat tire, he heard the two performing an impromptu set of Stanley Brothers songs to hold the audience at the packed club.

“I figured somebody had the jukebox playing our records,” he recalled in his 2009 memoir, “Man of Constant Sorrow,” written with Eddie Dean. “When I went inside, I saw it wasn’t no jukebox. It was two young gentlemen, standing onstage with a fiddle [Skaggs] and a guitar [Whitley], singing Stanley Brothers songs. They were just boys, not even old enough to start shaving yet. But they could pick like nobody’s business and they were singing their hearts out.”

Skaggs and Whitley, along with Randy Travis, in the 1980s would usher in a back-to-basics movement in country music known as neo-traditionalism. Skaggs in recent years has returned to bluegrass.

And in recent years, Mr. Stanley had himself become something of a standard-bearer for traditionalism in bluegrass.

Commenting on a 2006 performance by the Clinch Mountain Boys, New York Times music critic Ben Ratliff described Mr. Stanley’s singing as “ancient-sounding and dry as a biscuit” with “a modal style that runs between tones on a single word.”

Ratliff noted that in Mr. Stanley’s a cappella rendition of the hymn “O Death,” the word “death” at one point seemed to encompass six separate notes.

Ralph Edmond Stanley was born Feb. 25, 1927, near the mountain hamlet of McClure, Va.

The family was big — his older brother Carter plus seven older step-siblings. (Both parents had been previously widowed.) His father ran a sawmill and sang mountain ballads and hymns for his own enjoyment. He left the clan when Mr. Stanley was 12 to start another family with another woman in nearby Russell County.

Around that time, his mother bought a banjo for Mr. Stanley.

“She didn’t sing much, but she was one of 12 children and they all played the banjo some,” he told The Washington Post. “She taught me. But I was interested in animals too, and my aunt had a pig I wanted and also a banjo. They was each $5. Mother said she’d give me one or the other but I had to choose. So I took the banjo. Just as well I did.”

Carter played guitar, and the two brothers began performing at school and community gatherings — inspired by banjoist Wade Mainer, the Carter Family and other country musicians they heard on the radio. As high school graduation approached, the brothers decided to try a career in entertainment.

“We knew we didn’t want farm work and we darn sure didn’t want the mines,” Ralph Stanley told The Post. In 1946, they formed the Clinch Mountain Boys — named after a mountain ridge in their area — and performed on radio stations in southwestern Virginia. They were almost immediately popular with audiences and soon began making records.

He is survived by his wife of 47 years, Jimmie Stanley. He had three children, seven grandchildren and one great-grandchild, according to the AP.

A much wider audience was exposed to Mr. Stanley’s work through “O Brother Where Art Thou,” a Coen brothers film set in the Depression-era South and starring George Clooney as one of three chain-gang escapees who embark on a picaresque journey to recover treasure.

Producer T Bone Burnett had initially asked Mr. Stanley to perform “O Death,” a 19th-century dirge about a man’s plea with death, in the primitive style of Appalachian banjoist Dock Boggs. However, Mr. Stanley persuaded Burnette to let him perform it a cappella.

“I didn’t think the song needed a banjo,” Mr. Stanley said in his memoir. “It was getting in the way of the words and the meaning. I wanted to take that song back even further than Dock took it. I wanted to give it the old Primitive Baptist treatment.”

The song is heard coming from the mouth of an actor playing a hooded Klansman at a KKK rally — an effect that initially bothered Mr. Stanley, who later publicly endorsed Barack Obama for president in 2008.

The movie soundtrack, which also featured a vintage Stanley Brothers recording, “Angel Band,” received the 2001 Grammy Award for album of the year and sold millions of copies. In addition, Mr. Stanley received the best male country vocal Grammy for “O Death.”

The next year, Mr. Stanley, with Jim Lauderdale, received a Grammy for best bluegrass album, “Lost in the Lonesome Pines.” His other awards included a 2006 National Medal of Arts, the country’s highest honor for artistic excellence.

Mr. Stanley’s memoir, “Man of Constant Sorrow,” took its title from a song that had come to represent the joy he found in preserving the most traditional aspects of bluegrass music.

“ ‘Man of Constant Sorrow’ is probably two or three hundred years old,” he told NPR. “The first time I heard it, my daddy, he had some of the words to it and I heard him sing it. My brother and me, we put a few more words to it and brought it back into existence.

“If we hadn’t done that, it’d probably be lost forever,” he continued. “I’m proud to be the one who brought that song back because I think it’s wonderful. I try to sing it so plain that you can almost see what’s going on.”