Flann O’Brien is one of the pseudonyms of Brian O’Nolan, who was born in Ireland in 1911. He wrote satire for several satirical magazines during college, writing under other pseudonyms to disguise his identity. He later wrote a satirical column in the Irish Times, in which he criticized life in Dublin, his readers, and bureaucrats. Much of that journalism was published under the pseudonym Myles na Gopaleen. 

The use of pseudonyms and satirical background is important to the context of The Third Policeman. The narrator forgets his name early in the text, and the reader never learns it. However, he and Joe have extended conversations about potential names and identities for him: “Signor Beniamino Bari, Joe said, the eminent tenor” or “Dr. Solway Garr. The duchess has fainted. Is there a doctor in the audience?” (44). Given O’Brien’s well-known and extensive use of pseudonyms, the narrator’s focus on alternate names and identities is a self-aware and metafictional gesture toward the author’s reality.

O’Brien worked in the Irish Civil Service between 1935 and 1953. His longstanding tenure in a bureaucratic role is important to the novel’s satire of village policing and its depiction of hell as interminable and tedious bureaucracy. O’Brien’s first novel, At Swim-Two-Birds, was published in 1939 and he wrote The Third Policeman next. However, it was rejected by his publisher, who commented that he should make his writing less fantastical, not more so. He published a novel in Gaelic, The Poor Mouth in 1941, then two more novels in English—The Hard Life (1961) and The Dalkey Archive (1964)—during his lifetime. The Dalkey Archive contains some material repeated from The Third Policeman and features de Selby as one of its characters. The Third Policeman was published posthumously in 1967, after O’Brien’s death in 1966.