Leaving Jamaica in the early 1960s, he moved to Britain, where he freelanced as a broadcaster and journalist, also travelling and living elsewhere in Europe, before deciding to relocate to West Africa.

Barrett initially drew critical attention for his debut novel, Song for Mumu, which on its London publication in 1967 was favourably noticed by such reviewers as Edward Baugh and Marina Maxwell (who respectively described it as "remarkable" and "significant");[1] more recently it has been commended for its "pervading passion, intensity, and energy",[2] referred to as a classic,[3] and features on "must-read" lists of Jamaican books.

"[10][11] After graduating from high school in 1959 Barrett worked as an apprentice journalist at the Daily Gleaner[12] newspaper and for its sister afternoon tabloid, The Star.

While in Paris, he was associated with many notable black poets and artists, including Langston Hughes, Lebert "Sandy" Bethune,[18] Ted Joans,[19] Beauford Delaney and Herb Gentry.

[6] Writing in 2023 at the age of 82, Barrett would say: "I left Jamaica without informing any member of my family that I would do so in my nineteenth year and so my twenties were spent in absolute exile from the heart of my upbringing.

"[24] In February 1966, Barrett left Paris[25] to travel to Dakar, Senegal, for the first World Festival of Black Arts,[26] where – described by Negro Digest as "the fireball from Jamaica"[27] – he organised a poetry-reading session at the US Cultural Center.

He has been involved with many cultural initiatives, interacting with a wide range of African diaspora artists visiting Nigeria, including Ornette Coleman, Jimmy Cliff,[3] Jayne Cortez,[39] Melvin Edwards,[40] and others.

"[44] Barrett's first novel, Song for Mumu – "an allegorical novel of desire, love, and loss"[6] – was published to acclaim in 1967 in London, where he took part in readings alongside writers associated with the Caribbean Artists Movement.

"[47] Song for Mumu was one of the first titles published in 1974 by executive editor Charles Harris at Howard University Press in the US,[48] where it was received favourably by critics such as Martin Levin of The New York Times, who commented that "What shines ... is its language.

[50] More recently, Al Creighton writing in the Stabroek News referred to Song for Mumu as an "intriguingly poetic experimental novel", in the context of seeing Barrett as a disciple of Nigerian writer Gabriel Okara, "the virtual father of modern African literature in English".

[52] Barrett's second novel, Lipskybound, was published in Enugu, Nigeria, in 1977, and has influenced the work of many younger Nigerian writers who are interested in breaking the mould of traditional creative writing.

Jump Kookoo Makka was presented at the Leicester University Commonwealth Arts Festival in 1967 (directed by Cosmo Pieterse) and that same year Home Again was performed by Wole Soyinka's company.

– an exploration of Caribbean history through music, mime and dance – was performed in London, the first play by a Black writer at the Institute of Contemporary Arts[55] (with an all-Black cast,[56] including Yemi Ajibade, Yulisa Amadu Maddy, Leslie Palmer, Eddie Tagoe, Karene Wallace, Basil Wanzira, and Elvania Zirimu, directed by Horace Ové)[57] and filmed for a special edition of the BBC 2's arts and entertainment programme Full House (broadcast on Saturday, 3 February 1973) devoted to the work of West Indian writers, artists, musicians and filmmakers.

was described as "ritual theatre with music and dance" that "expresses in terms of raw bodily experience the history of the Black peoples of the world through colonization, slavery and the complexities of the neocolonialist era".

[61] In 1972, his theatrical collage of drama, dance and music, Sighs of a Slave Dream, was the first major production to be staged at the Keskidee Centre, in north London, performed by a Nigerian troupe under the direction of Pat Amadu Maddy.

That same year he produced a staged version of Linton Kwesi Johnson's poem Voices of the Living and the Dead at London's Keskidee Centre, with music by the reggae group Rasta Love.

As a journalist, Barrett has written on the conflicts and ongoing political circumstances in Liberia[72] and Sierra Leone,[73][74] and was the co-founder, with Tom Kamara, of the Liberian newspaper The New Democrat.

[94] Barrett is a contributor to the 2024 book Encounters with James Baldwin: Celebrating 100 Years (Supernova Books/Aurora Metro), with other featured writers including Anton Phillips, Fred D'Aguiar, Rashidah Ismaili AbuBakr, Ray Shell, and others.