"Black Night" is a song by British hard rock band Deep Purple, first released as a single in June 1970 and later included on the 25th Anniversary version of their 1970 album, In Rock. The song became a hit following its release, peaking at No. 2 on UK charts, and to this day remains Deep Purple's highest charting UK single. It topped the charts in Switzerland, and is one of only two singles from the band to chart in Ireland, peaking at No. 4, thus making it the group's only Irish Top 10 hit. It was also the first single penned by the band. Once In Rock had been completed, EMI asked for a suitable single to be recorded to help promote the album. Though Roger Glover claims that Ricky Nelson's 1962 hard rocking arrangement of the George Gershwin classic "Summertime" was the basis for the Mk II Deep Purple single "Black Night", it is also similar to Blues Magoos's 1966 psychedelic hit song "(We Ain't Got) Nothin' Yet". In the BBC documentary "Heavy Metal Britannia" keyboardist Jon Lord supports Glover's statement about the song's origin stating "Black Night was nicked from the bassline in Ricky Nelson's Summertime" and then proceeds to play the bassline riff on his grand piano.