Bill Monroe , byname of William Smith Monroe (born Sept. 13, 1911, Rosine, Ky., U.S.—died Sept. 9, 1996, Springfield, near Nashville, Tenn.), American singer, songwriter, and mandolin player who invented the bluegrass style of country music.

The youngest of eight children of a Kentucky farmer and entrepreneur, Monroe was exposed early to traditional folk music by his mother. Another important early musical influence on the young Monroe was Arnold Schultz, a local African American miner who also was an accomplished fiddler and guitarist and who played both blues and country music. Monroe began playing the mandolin professionally in 1927 in a band led by his older brothers Birch and Charlie. In 1930 they moved to Indiana, and in 1932 they joined a barn-dance touring show; their reputation grew, but, because Birch did not like to travel, Bill and Charlie maintained the Monroe Brothers as a duo, touring widely from Nebraska to South Carolina. In 1936 they made their first recordings on the RCA Victor label, and they recorded 60 songs for Victor over the next two years. In 1938 Bill and Charlie decided to form separate bands. Bill’s second band, the Blue Grass Boys (his first, called the Kentuckians, played together for only three months), auditioned for the Grand Ole Opry on radio station WSM in Nashville, Tenn., and became regular performers on that program in 1939.

Monroe’s signature sound emerged fully in 1945, when banjoist Earl Scruggs and guitarist Lester Flatt joined his band. Scruggs was among the first banjoists in country music whose principal role was musical rather than comical; Monroe’s original banjoist David (“Stringbean”) Akeman had provided a humorous touch to the proceedings. The Blue Grass Boys established the classic makeup of a bluegrass group—with mandolin, fiddle, guitar, banjo, and upright bass—and ultimately bequeathed the band’s name to the genre itself. Bluegrass is characterized by acoustic instruments; a driving syncopated rhythm; tight, complex harmonies; and the use of higher