[2][3][4] Born in Brooklyn, New York City, to an African-American father from South Carolina and a Bahamian mother, Williams enrolled at the National Black Theater.

His distinctive voice, prominent facial scar, and charisma helped him obtain acting work, initially alongside Tupac Shakur in the 1996 film Bullet before being cast in The Wire in 2002.

[8] Williams was raised on New York Avenue near Vanderveer Projects in East Flatbush, Brooklyn,[9][10] and attended George Westinghouse Career and Technical Education High School.

[13] However, inspired by Janet Jackson's Rhythm Nation 1814, he left school and quit his job, against the wishes of his family, to pursue a career as a dancer.

The scar became his signature feature, and resulted in offers to perform as a thug in music videos[16] and modeling opportunities with noted photographers like David LaChapelle.

[20] However, creator David Simon stated that they always planned to keep the character as part of the continuing ensemble should the show be renewed beyond one season.

[24] Williams received both positive and negative reactions to Omar's homosexuality and felt that he was successful in challenging attitudes and provoking discussion with the role.

[24] Williams played Teddy, the former boyfriend of Nikki Tru (Kerry Washington) in the Chris Rock film I Think I Love My Wife.

Williams starred in HBO's Boardwalk Empire for its five seasons (2010–2014), appearing as Albert "Chalky" White, the leader of 1920s' Atlantic City's black community.

[34] Williams, who had previously confirmed that he was actually in talks with Tarantino to take on the titular role of Django, was to portray a minor character in the film, but scheduling conflicts with Boardwalk Empire prevented him from doing so.

[36] Williams also shared on The Breakfast Club that he was starring in an African American western, They Die by Dawn, with his co-star Snoop from the HBO series The Wire.

Williams mentioned the role was special to him because he grew up listening to Ol' Dirty Bastard and to Wu-Tang and was also a Brooklyn native.

On March 9, 2015, it was announced that Williams would star in SundanceTV's Hap and Leonard,[41] and he stayed with the series for its entire three-season run.

[44] Williams was originally cast as Dryden Vos, a crime lord, in Solo: A Star Wars Story,[45] but exited the role after being unable to return for re-shoots due to scheduling conflicts with the film The Red Sea Diving Resort.

[53][54][55][18] On September 24, the Chief Medical Examiner of New York City ruled it a death by overdose and confirmed that Williams died of a combination of cocaine, fentanyl, heroin, and parafluorofentanyl.

[61] In April 2023, drug dealer Irvin Cartagena pleaded guilty to selling the mix of heroin and fentanyl to Williams that resulted in his death.

[63][64] Williams also served as the American Civil Liberties Union celebrity ambassador to the Campaign for Smart Justice.

[68] His performance as Omar was widely-acclaimed, leading to praise from President Barack Obama and a nomination for NAACP Image Award for Outstanding Actor in a Drama Series in 2007.

[23] With The Wire and other shows such as The Sopranos, Williams was credited with being part of the late 1990s and early 2000s artistic force changing American television into an art-form.

[69] In the aftermath of his death, he was the subject of tributes and appraisal both in the United States and beyond; the British lecturer and writer Kenan Malik wrote of his "power and nuance, seldom seen on screen".