Keith Emerson was an English musician and composer. He played keyboards in a number of bands before he found his first commercial success with the Nice, formerly P. P. Arnold's backing band, in the late 1960s. He became internationally famous for his work with the Nice, which included writing rock arrangements of classical music. After leaving the Nice in 1970, he was a founding member of Emerson, Lake & Palmer (ELP), one of the early progressive rock supergroups. Emerson, Lake & Palmer were commercially successful through much of the 1970s, becoming one of the best-known progressive rock groups of the era.