Few rock bands can lay claim to as many innovations as The Byrds. The L.A. group played a crucial role in the creation of folk-rock with their electrified versions of songs by Pete Seeger and Bob Dylan. They were early adopters of psychedelia as well, and it was their groundbreaking Sweetheart of the Rodeo, featuring Gram Parsons, that provided the blueprint for most country-rock to follow. Frontman Roger McGuinn was the only constant member of the ever-evolving outfit, though David Crosby, Gene Clark, and Chris Hillman all played an important part in the band's history.