It was initially released as their debut single by the Drowned In Sound label on 17 May 2004, reaching #66 in the UK charts. "Oh My God" was re-released on 21 February 2005, just two weeks before the release of their debut album Employment. This time, it peaked at #6 in the UK charts, which earned the band their first top 10 hit, as well as being their highest-charting single at the time until it was succeeded by UK chart-topper "Ruby" on 25 February 2007. The song also appeared on the soundtrack for the video game Driver: Parallel Lines.

The original single release, now a rarity due to its limited run of 500 copies, features artwork by frontman Ricky Wilson, and its B-sides were earlier versions of "Born to Be a Dancer" and "Caroline, Yes", both of which would also appear on Employment.

All of these tracks are different, earlier versions of the album editions.

In 2006, "Oh My God" was covered by Lily Allen on her second mixtape. Allen later re-recorded the track with Mark Ronson for his second studio album Version (2007), and then went on to become the second single release from the album that same year. The single was a success, reaching the UK Top 10. It was released as the album's first single in Brazil, due to Lily Allen's success in that country.

The music video was directed by Nima Nourizadeh, and features a cartoon version of Allen (a reference to Jessica Rabbit in the film Who Framed Roger Rabbit) performing the song and flirting in the Ink and Paint Club. The Kaiser Chiefs themselves make a cameo. Of notice is that, in the video, "Lily Allen" is the only toon present. Most of the toons that worked at the club (the octopus bartender, the penguin waiters, Bongo the Gorilla and Betty Boop) have been replaced by real people.

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Wikipedia