the book was published in 1933. it only became popular after hilton's next book, "goodbye, mr. chips", was published in 1934. "lost horizon" then became a huge success. in 1939, it was published in paperback, as pocket book #1. because of its number-one position in what became a very long list of pocket editions, "lost horizon" is often called the first american paperback book. this is not correct. the first pocket-sized, paperback book sold in many stores in america was pearl buck's "the good earth" by pocket books in 1938 as an experiment.