G-Unit (short for Guerilla Unit) is an American hip hop group originating from South Jamaica, Queens, New York, formed by longtime friends and East Coast rappers 50 Cent, Tony Yayo and Lloyd Banks. The group released their debut album Beg for Mercy, in 2003, which went on to sell over 2,000,000 copies in the US and was certified Double Platinum by the Recording Industry Association of America (RIAA). The album, which followed the critical and commercial success of 50 Cent's major-label debut Get Rich or Die Tryin', served as a platform for Lloyd Banks, Young Buck and Tony Yayo to release their respective solo debut albums; The Hunger for More (2004), Straight Outta Cashville (2004) and Thoughts of a Predicate Felon (2005). In 2008, the group released their second album T*O*S (Terminate on Sight).

50 Cent signed to Interscope Records. Due to the success of his commercial debut album, Get Rich or Die Tryin', he was granted his own record label. This was when G-Unit Records was created. G-Unit gained more popularity when a remix to 50 Cent's "P.I.M.P." was released, featuring Snoop Dogg and G-Unit. But before the group had a chance to record its debut album, Tony Yayo was sentenced to prison for a gun-possession charge as well as bail-jumping. During Tony Yayo's prison sentence, 50 Cent signed Tennessee-based rapper Young Buck to G-Unit Records and subsequently added him to the group. In 2003, the group's debut album Beg for Mercy, was released. However, while the album was being recorded, Tony Yayo was sentenced to jail on charges of gun possession. Therefore, he only makes two appearances, both were pre-recorded tracks. His face is seen on the brick wall of the album cover because he could not be photographed on account of his jail sentence. Beg for Mercy went on to sell 2.3 million copies in the US and 4 million copies worldwide. The only guest appearances on the album were R&B singers Joe and Butch Cassidy. The album's production was handled by high-profile producers such as Hi-Tek, Dr. Dre and Scott Storch, among several others. 50 Cent also served as the album's executive producer. West Coast rapper The Game was originally placed into G-Unit by Dr. Dre and Jimmy Iovine of Interscope Records. Their plan was to market The Game as a devotee, or a card-carrying member of 50 Cent's "camp.". However, after a while, tensions began to rise between The Game and 50 Cent. 50 Cent also claimed that he did not receive proper credit for co-writing most of the songs on Game's debut album The Documentary (2005).

What other success did they have during this time period?
G-Unit gained more popularity when a remix to 50 Cent's "P.I.M.P." was released, featuring Snoop Dogg and G-Unit.