To a God Unknown is a novel by John Steinbeck, first published in 1933. The book was Steinbeck's second novel. Steinbeck found To a God Unknown extremely difficult to write; taking him roughly five years to complete, the novel proved more time-consuming than either East of Eden or The Grapes of Wrath, Steinbeck's longest novels.

John Ernst Steinbeck was an American writer. He won the 1962 Nobel Prize in Literature "for his realistic and imaginative writings, combining as they do sympathetic humor and keen social perception". He has been called "a giant of American letters."