Interested in rap from a young age, Eminem began performing as early as 13, later gaining some popularity with the group Soul Intent. In 1996, he released an independent underground album named Infinite The album received much airplay and a mixed critical response, with people claiming Eminem's rapping style sounded too similar to Nas and Az. It was after this that drugs, drama and negativity spread in his life.

Mathers followed Infinite with The Slim Shady EP demo, which saw his lyrics take a decidedly darker turn, in songs like "No One's Iller" and "Murder Murder", the latter in which he talks about having to commit crimes to feed his daughter. He became famous in the hip-hop underground because of his distinctive, cartoonish style and the fact that he was white in a predominantly black genre. Fellow rapper Snoop Dogg refers to him as rap's "great white American hope" in the song "Bitch Please II" on Eminem's Marshall Mathers LP. Eminem had done a notable amount of work with fellow Detroit emcee Royce da 5'9" early in his career. They referred to themselves as Bad Meets Evil, with Eminem playing the evil and Royce playing the bad in the song of the same name on The Slim Shady LP. Royce da 5'9" and Eminem were considered to be two of the best underground emcees in Detroit and were both respected for their battling skills.

The Jay-Z song "Renagade" uses Eminem's verses from a song originally done with Royce called "Renegade". The song's first verse ends with the words, "Royce, he's the king of Detroit..." which was replaced with Eminem making beat box noises for Jay-Z's "Renagade" (note that the two songs are spelled slightly differently). Eminem makes a reference to Jay-Z using his verses in a song when he claims "Go bring Jay-Z, tell him I'm a ghost-write for him on Dre's beats" from "Stir Crazy" that he recorded with The Madd Rapper. While the two were great friends and had mutual respect for one another both personally and musically, they eventually had a falling out. Royce later had an altercation with D12 and made numerous songs defaming and disrespecting the group; however, very few lines were aimed at Eminem himself, none of which were direct attacks.

The relationship between the two is unknown at the moment but no talks of a collaboration have surfaced. Recent rumors suggest that the argument was subdued prior to Proof's death. It is said that rap artist and producer Dr. Dre found Mathers' demo on Interscope Records president Jimmy Iovine's garage floor. While this did not directly lead to a recording contract, Dr. Dre agreed to sign Mathers when he won second place versus Otherwise, (though some sources say it was, in fact, MC Juice who defeated him) at the 1997 Rap Olympics freestyle battle. Other sources state that an executive at the offices of Interscope handed the demo to Iovine who passed it to Dre, which resulted in a contract.

At Aftermath/Interscope, Mathers released The Slim Shady LP, which went on to be one of the most popular albums of 1999, going triple platinum by the end of the year. It moved nearly 1.5 million units in its opening week. With the album's enormous popularity came controversy surrounding many of the album's lyrics. In "'97 Bonnie and Clyde", he describes a trip with his infant daughter, disposing of the body of his wife. Another song, "Guilty Conscience," ends with him encouraging a man to murder his wife and her lover. "Guilty Conscience" also marked the beginning of the powerful friendship and musical bond that Dr. Dre and Eminem would share. The two label-mates would later collaborate on a line of hit songs, including "Forgot About Dre" and "What's The Difference" from Dr. Dre's highly acclaimed album 2001. The Marshall Mathers LP was released in May 2000, quickly selling two million copies. It was the fastest selling rap album of all time. The first single released from the album, the hit: The Real Slim Shady, was a huge hit, thanks in part to the catchy rhythm and chorus line, "Will the real Slim Shady please stand up?" (adapted from the catch phrase of the TV quiz show To Tell the Truth). It also created some buzz by insulting celebrities and making dubious claims about them; he implies, among other things, that Christina Aguilera performed oral sex on Fred Durst (of Limp Bizkit) and Carson Daly (of MTV's Total Request Live). "The Real Slim Shady" is widely considered to be Eminem's "signature" and best commercial single. In his second single, "The Way I Am," he reveals to his fans the pressures from his record company to top "My Name Is" and sell more records, and dismisses the alleged controversial link between music such as that of Marilyn Manson and shootings such as Columbine High School as absurd, instead blaming the parents.

In the third single, "Stan" (which samples Dido's "Thank you"), Eminem attempts to deal with his new-found fame, taking on the perspective of a deranged fan who kills himself and his pregnant girlfriend, mirroring "'97 Bonnie & Clyde" on The Slim Shady LP. To this date, "The Marshall Mathers LP" is widely considered to be Eminem's greatest achievement, and a hip-hop classic. Mathers' third major album, The Eminem Show, was released in summer 2002 and proved to be another smash hit for the rapper shooting to number one on the charts and selling well over 1 million copies in its first week of release. It featured the single "Without Me", an apparent sequel to "The Real Slim Shady", in which he makes derogatory comments about boy bands, Limp Bizkit, Moby, and Lynne Cheney, among others.

The album reflected on the impact of his rise to fame, his relationship with his wife and daughter, and his status in the hip-hop community. He also addresses the charges he faced over assaulting a bouncer he saw kissing his wife in 2000. While there is clear anger present on several tracks, this album was considerably less inflammatory than the previous, and as such did not face any protests of misogyny and homophobia that had plagued The Marshall Mathers LP. 2004 saw the release of Mathers' fourth major album, Encore. The album was another chart-topper for the rapper, driven by the formulaic single "Just Lose It", notable for its lampooning of Michael Jackson. Despite the comedic theme of the lead single, Encore also had its fair share of serious subject matter, including the poignant anti-war track "Mosh". By the end of 2005 Mathers was back with a new single, "When I'm Gone", recorded for the greatest-hits set Curtain Call: The Hits. 

Eminem has had 13 number one singles worldwide. In December 2009 Eminem was named the Artist of the Decade by Billboard magazine. His albums The Eminem Show, The Marshall Mathers LP, and Encore (in order) ranked as the 3rd, 7th, and 40th best album of the 2000-2009 decade by Billboard magazine. According to Billboard, Eminem has two of his albums among the top five highest selling albums of the 2000s. In the UK, Eminem has sold over 12.5 million records. In the US, Recovery sold 741,000 in its first week to land atop the Billboard 200. The first single, "Not Afraid", was released on April 29, and debuted at number one on the Billboard Hot 100, followed by a second single, "Love the Way You Lie," which reached number 2.