One Nation Under a Groove is the tenth studio album by American funk rock band Funkadelic, released on September 22, 1978, on Warner Bros. Records.

Recording sessions took place at United Sound Studio in Detroit, with one song recorded live on April 15, 1978, at the Monroe Civic Center in Monroe, Louisiana.

One Nation Under a Groove was Funkadelic's most commercially successful album, reaching number 1 on the Billboard Magazine Top R&B/Hip-Hop Albums chart, number 16 on the Billboard 200, and being certified platinum in the US.

[16] According to the academic Bill Martin, One Nation Under a Groove is indebted "a good deal more to progressive rock than most critics are willing to admit, as well as progressive soul, Hendrix, and Sly Stone".

[18] In Europe, the Bonus-EP was replaced by a bonus 12-inch 45rpm mini-album containing the 3 EP tracks on one side and an extended version of "One Nation Under a Groove" on the other.