The Man Who Went Back (1940) is an adventure novel by Warwick Deeping about a man who has a car accident in 1939 England. He is transported back into post-Roman Britain and has to contend with the knowledge that he is from the future, in the past.
Upon release, the New York Times described the book as a "remarkable merger" of Deeping's prior novels with "cloak-and-sword" settings and those set in contemporary times, resulting in an "odd but earnest novel."