"The National Anthem" is the third track from the alternative rock band Radiohead's 2000 album Kid A. The song is moored to a repetitive bassline, has a processed electronic production, and develops in a direction influenced by jazz. It has been played at nearly every Radiohead concert since 2000.
The National Anthem is thought to have been previously attempted at recording sessions in 1994 and 1997, but according to Radiohead member Colin Greenwood, the band decided it was "too good to use it as a b-side for OK Computer singles". In the album recording, the bass is played by lead singer Thom Yorke, who wrote the riff at age 16.
In the recording sessions, band members Thom Yorke and Jonny Greenwood conducted the session musicians, though Yorke lacks formal musical training. Yorke stated in an interview, "The running joke when we were in the studios was, 'Just blow. Just blow, just blow, just blow'", referring to the chaotic brass section sound. Although the recording sounds chaotic, each instrument is playing a solo to the riff.
The free jazz-style brass section featured in the song, influenced by Charles Mingus, creates a soundscape of chaos, and has been described as "a brass band marching into a brick wall" by one reviewer.
The song also features an Ondes Martenot, played by Jonny Greenwood, an early electronic instrument which was picked up by Greenwood for several songs on Kid A and subsequent albums. Greenwood's usage of it was inspired by the music of Olivier Messiaen.
"The National Anthem" was the opening song for most Radiohead concerts in 2000–2001, and is the first track on the band's 2001 album I Might Be Wrong: Live Recordings.