"Clint Eastwood" is named after the famous movie actor. The theme from The Good, The Bad, and the Ugly can be heard periodically throughout the song; this was one of several Sergio Leone-directed Italian westerns of the late 1960s in which Eastwood plays a character with no name. Eastwood also famously played Dirty Harry Callahan in a series of five films, and was the Mayor of Carmel, California in the 1980s. Eastwood is also a huge fan and supporter of jazz, and is an accomplished self-taught jazz pianist. Years after the release of this album, It was revealed that the track "Starshine" has an alternative version, which features Luton-based rap group Phi Life Cypher. This version is not available on any releases, but it is available on the Phi Life Cypher SoundCloud channel and also on the video-sharing website YouTube.
All editions of the Gorillaz album feature an enhanced section that included screen savers, wallpaper and an autoplay, featuring a short movie which opens the user's Internet browser to a special section of the Gorillaz website, which gives the user full access to Murdoc's Winnebago.
Del the Funky Homosapien collaborated on two songs on the album, "Clint Eastwood" and "Rock the House", both of which became singles and videos and achieved chart success. Del was not, however, originally slated to collaborate on these songs. By the time Del came onto the project, the album was already finished, and Phi Life Cypher had recorded verses for "Clint Eastwood"; but when Del finished making Deltron 3030 with Dan the Automator, Automator asked if he could stay in the studio a little longer to record new verses for the Gorillaz songs. For the purposes of the music videos and the Gorillaz storyline canon, Del performed as Gorillaz character "Del the Ghost Rapper", who was said to be a spirit that was hiding from death within the band's drummer, Russel Hobbs. Del later commented in an interview on the success of "Clint Eastwood" by saying that he actually wrote the song with the book How to Write a Hit Song, a book that he bought with a coupon his mother gave him. After the song went platinum he gave the plaque to his mother. As part of Russel Hobbs' back-story, the character of Del was one of Russel's friends that was gunned down in a drive-by shooting, whose ghost possessed Russel.
In 2004, the album was packaged with 2002's Laika Come Home in a limited edition box set as part of EMI's "2CD Originals" collection. Other saw a release such as the reggae-dub "Dub Dumb", which features British-Jamaican artist Sweetie Irie; it is available on the PlayStation 2 game MTV Music Generator 2 rather than on G Sides or the album itself. Other tracks include "Gor Beaten", which was another track that didn't make the album; however, elements of the track's instrumental were once available on one of the Gorillaz member's computers in Kong Studios.
Gorillaz received generally positive reviews from critics, with the exception of Rolling Stone. It was ranked number six in Spin's Albums of the Year 2001, ranked number 96 in Slant magazine's best of the 2000s list,Complex magazine ranked it in the top 100 albums of the 2000s, and Gigwise included it on their list the 19 best self titled albums of all time.
Q listed the album as one of the best 50 albums of 2001.
"Tomorrow Comes Today" was released as an EP before the album was released. A video for the single was also released.
"Clint Eastwood" was the first single from the album, debuting on 4 March 2001. The single peaked at number four on the UK Singles Chart, number 57 on the Billboard Hot 100 and number three on the Billboard Hot Modern Rock Tracks chart.
"19-2000" was the second single from the album, released in June 2001. The single peaked at number six on the UK Singles Chart and number 23 on the Billboard Hot Modern Rock Tracks.
"Rock the House" was the third single from the album, released in October 2001. The single peaked at number 18 on the UK Singles Chart.
"Tomorrow Comes Today" was the fourth and final single from the album, released almost a year after the album, in February 2002. It peaked at number 33 on the UK Singles Chart.
"5/4" was repeatedly considered for a single but was edged out by "19-2000" and "Rock the House". A video was considered for this, but never got past the storyboarding stage.