Crosby, Stills & Nash was a folk-rock supergroup comprising American singer-songwriters David Crosby and Stephen Stills and English singer-songwriter Graham Nash. When joined by Canadian singer-songwriter Neil Young, they were known as Crosby, Stills, Nash & Young. They are noted for their intricate vocal harmonies and lasting influence on American music and culture, their political activism and their tumultuous relationships.
CSN formed in 1968 shortly after Crosby, Stills and Nash performed together informally, discovering they harmonized well. Crosby had been asked to leave the Byrds in late 1967, Stills' band Buffalo Springfield had broken up in early 1968, and Nash left his band the Hollies in December. They signed a recording contract with Atlantic Records in early 1969. Their first album, Crosby, Stills & Nash produced the Top 40 hits "Suite: Judy Blue Eyes" and "Marrakesh Express". In preparation for touring, the trio added Young, Stills' former Buffalo Springfield bandmate, as a full member, along with the touring members Dallas Taylor and Greg Reeves. As Crosby, Stills, Nash & Young, they played the Woodstock festival that August.