King Rat is a 1962 novel by James Clavell. Set during World War II, Clavell's literary debut describes the struggle for survival of British, Australian and American prisoners of war in a Japanese camp in Singapore — a description informed by Clavell's own three-year experience as a prisoner in the notorious Changi Prison camp. One of the major characters, "Peter Marlowe," is based upon Clavell's younger self.

Despite its fearsome reputation, Changi was historically among the better-run Japanese camps, with only 850 deaths among the 87,000 prisoners who passed through^[1].

King Rat was retroactively made the first book in Clavell's sweeping series, the Asian Saga. Several main characters from King Rat appear again in Noble House.