Manchild in the Promised Land is Claude Brown's semi-autobiographical account of growing up in Harlem in the 1940s and 1950s. He drew from his own life and added some fictional elements in a coming-of-age story that presents the reality of what it was like for the first generation of African American young people to grow up in the north after their parents had left the South during the Great Migration.

Part of the background of the story is the way in which the author felt that his generation was a "misplaced generation." Claude Brown was born in Harlem in 1937, three years after his parents had left the South. His protagonist, Sonny, is similarly misplaced, and he feels that his parents can not offer him any guidance. His mother takes a resigned attitude, while his father is largely indifferent. Sonny feels that they are too subservient to white people.

Brown's book explores the sociological and demographic variables, including hopeless and poverty, that created crime in places like Harlem. Brown documents Sonny's involvement in gangs who he feels could better orient him to life in the urban north and his introduction to the dangers of that life, including drugs and crime. At only 13, Sonny is shot while caught in a burglary, and he is sent to the Wiltwyck Reformatory, where an administrator named Ernest Papanek urges him to get an education. Although he sees the people in the world around him descend into drugs, thievery, and prostitution, he is saved through a combination of luck and his interactions with people like Papanek. The book is the story of a boy's descent into a kind of urban hell and his salvation by choosing a path in life that is different from those around him.