The sixth generation of country music continued to be influenced by other genres such as pop, rock, and R&B. Richard Marx crossed over with his Days in Avalon album, which features five country songs and several singers and musicians. Alison Krauss sang background vocals to Marx's single "Straight from My Heart." Also, Bon Jovi had a hit single, "Who Says You Can't Go Home", with Jennifer Nettles of Sugarland. Kid Rock's collaboration with Sheryl Crow, "Picture," was a major crossover hit in 2001 and began Kid Rock's transition from hard rock to a country-rock hybrid that would later produce another major crossover hit, 2008's "All Summer Long." (Crow would also cross over into country with her hit "Easy.") Darius Rucker, former frontman for the 1990s pop-rock band Hootie & the Blowfish, began a country solo career in the late 2000s, one that to date has produced three albums and several hits on both the country charts and the Billboard Hot 100. Singer-songwriter Unknown Hinson became famous for his appearance in the Charlotte television show Wild, Wild, South, after which Hinson started his own band and toured in southern states. Other rock stars who featured a country song on their albums were Don Henley and Poison.
Country pop or soft pop, with roots in the countrypolitan sound, folk music, and soft rock, is a subgenre that first emerged in the 1970s. Although the term first referred to country music songs and artists that crossed over to top 40 radio, country pop acts are now more likely to cross over to adult contemporary music. It started with pop music singers like Glen Campbell, Bobbie Gentry, John Denver, Olivia Newton-John, Anne Murray, B. J. Thomas, The Bellamy Brothers, and Linda Ronstadt having hits on the country charts. Between 1972 and 1975, singer/guitarist John Denver released a series of hugely successful songs blending country and folk-rock musical styles ("Rocky Mountain High", "Sunshine on My Shoulders", "Annie's Song", "Thank God I'm a Country Boy", and "I'm Sorry"), and was named Country Music Entertainer of the Year in 1975. The year before, Olivia Newton-John, an Australian pop singer, won the "Best Female Country Vocal Performance" as well as the Country Music Association's most coveted award for females, "Female Vocalist of the Year". In response George Jones, Tammy Wynette, Jean Shepard and other traditional Nashville country artists dissatisfied with the new trend formed the short-lived "Association of Country Entertainers" in 1974; the ACE soon unraveled in the wake of Jones and Wynette's bitter divorce and Shepard's realization that most others in the industry lacked her passion for the movement.
By the end of World War II, "mountaineer" string band music known as bluegrass had emerged when Bill Monroe joined with Lester Flatt and Earl Scruggs, introduced by Roy Acuff at the Grand Ole Opry. That was the ordination of bluegrass music and how Bill Monroe became to be known as the "Father of Country Music." Gospel music, too, remained a popular component of bluegrass and other sorts of country music. Red Foley, the biggest country star following World War II, had one of the first million-selling gospel hits ("Peace in the Valley") and also sang boogie, blues and rockabilly. In the post-war period, country music was called "folk" in the trades, and "hillbilly" within the industry. In 1944, The Billboard replaced the term "hillbilly" with "folk songs and blues," and switched to "country" or "country and Western" in 1949. https://www.youtube.com/watch?v=hyNAvdnZ5Ec