James Tapp was raised in the Magnolia Projects. He attended Booker T. Washington High School before dropping out of school in his sophomore year. Tapp released his debut album, Soulja fa Lyfe, on Parkway Pumpin' Records in 1994 under the name Magnolia Slim. In 1995, he released the four-song e.p. The Dark Side on Hype Enough Records.
In the same year, the song "You Got It" appeared on No Limit Records double-CD compilation Down South Hustlers: Bouncin' and Swingin' . In 1998, Tapp, now calling himself Soulja Slim, released Give It 2 'Em Raw on No Limit Records with his single and music video "From What I Was Told" and a single called "Street Life". Soulja Slim was convicted of armed robbery and incarcerated. He reappeared three years later with Streets Made Me, which was again released on the No Limit label. From there, he started his own label, Cut Throat Committee Records and released Years Later in late 2002. In 2003, he released Years Later...A Few Months After, his last album before his death. The album featured the hit "I'll Pay for It". In 2003 he also collaborated with fellow New Orleans rapper Juvenile to make the song "Slow Motion". The song was released on Juvenile's album Juve the Great and reached the No. 1 spot on the Billboard Hot 100. It was Soulja Slim and Juvenile's first No. 1 hit, and as the song was released after Soulja Slim's death he became only the sixth artist to have a posthumous No. 1 song.
On Thanksgiving Eve, November 26, 2003, an unknown gunman shot him four times; three times in the face, and once in the chest, in the front lawn of his mother's home located in the 4600 Lafaye St. in the Gentilly neighborhood.  Soulja Slim was buried with his Cut Throat Comitty charm and jewelry and also the leather camo clothes he wore on the cover of Give It 2 'Em Raw. On New Year's Eve, December 31, 2003, police arrested 22-year-old Garelle Smith in connection with Tapp's murder. Police discovered a stolen police pistol in Smith's possession with a scratched-off serial number. A ballistics test matched bullets from that gun to the ones that killed Soulja Slim but no witnesses would testify against him. By 2008 Smith had been arrested for three more murders and in each case, charges were dropped and he was released due to lack of witnesses and the New Orleans 60 day law. Along with the other murders, the District Attorney's Office dropped the Soulja Slim murder charge against him and his death became a cold case. In August 2011, Smith himself was found dead with gunshot wounds to the face and chest.