After World War II ended, Allen studied at The New School for a year and then went to Paris on the G.I. Bill, studying at the Sorbonne from 1948 to 1949.[2][1][3] His first poems appeared in 1949 in Présence africaine and his first book of poetry was published in 1956.[1][3] He edited English writing in Présence africaine after Richard Wright left France.[4] His 1959 essay "Negritude and Its Relevance to the American Negro Writer" was published in the journal and widely reprinted.[4]
He worked as a lawyer in government and private practice from the 1940s to 1960s, before being appointed as the Avalon Professor of Humanities at the Tuskegee Institute (now Tuskegee University) in 1968.[2] From 1971, he taught literature at Boston University.[2]
Allen's work was not well known in the United States until the 1960s, when it was published in anthologies edited by Arna Bontemps and Langston Hughes.[4] His 1975 poetry collection Paul Vesey's Ledger "traces the long history of oppression against African Americans".[5]