Ellison gained valuable writing experience while working for the Federal Writers' Project between 1938 and 1942. Through his work, he came into close contact with a variety of people and thus became better adept at producing realistic characters in his writing. Many of the conversations he recorded he then used when he was writing The Invisible Man. For instance, Mary Rambo's character advises the narrator of the novel to not let New York corrupt him. This quotation is verbatim out of his FWP encounters. Another experience which was later encapsulated into his novel was his work in freelance writing. In 1943, he was hired to cover a riot in Harlem. This event provided the background for the climax of the novel, the race riot, which finally succeeds in driving the narrator underground in The Invisible Man.
While in the Merchant Marines during World War II, Ellison struggled with writing a prison camp novel. He contracted a kidney infection and became depressed. He took a sick leave as the War wound down in 1945 and moved with his wife to recuperate in Vermont. He spent time reading Lord Raglan's The Hero which discusses African-American mythical and historical figures. Also influenced by the likes of Sophocles, Homer, Dostoyevsky, Freud, Jung, Wright, and others, he began to think about black leaders and wondered why they ignored their constituents but often bent over backwards for the white man. He decided to write a novel about black identity, heroism, and history through the use of the folklore, spirituals, blues, comedians, archetypes, and personal experiences he had gathered over the years. One day in 1945, Ellison sat at his typewriter in Vermont, thinking of an ironic joke he had heard from a black face comedian about his family becoming so progressively dark in complexion that the new baby's mother could not even see her. In this vein, he suddenly wrote, "I am an invisible man". He nearly rejected the idea but was intrigued and decided to give it a try. Ellison then spent seven years working on the novel, The Invisible Man.
In October of 1947, Ellison published the battle royal chapter as "Invisible Man" in the British magazine, Horizon. In 1948, he published the same section in the American magazine, Magazine of the Year. Subsequently, in the early months of 1952, he published the Prologue of the novel in the Partisan Review. The complete novel was then published in April of 1952. It received favorable reviews by both white and black audiences, although it was also met with some negative reviews. Harsh criticism came from a minority of the Afro-American community who claimed that the novel displayed contempt toward blacks. The Left also was a harsh critic, finding the novel to be pretentious and otherworldly. Overall however, the book was greeted positively. Over the years it has been awarded with numerous accolades, such as the Russwurm Award, National Book Award, Rockefeller Foundation Award, and Prix de Rome Fellowships from the American Academy of Arts and Letters.