Tarzan and the Foreign Legion was published in 1947 and is the last Tarzan novel Burroughs completed before his death. The setting is the Pacific Theater of the Second World War rather than Africa. Tarzan has been seconded to the Royal Air Force as Colonel John Clayton, partly because of his fluency in jungle survival and his command of African languages. His plane crashes in Japanese-occupied Sumatra.
Tarzan and the surviving crew, eventually including a Dutch resistance fighter and a downed Australian gunner, spend the rest of the novel evading Japanese patrols, working with local resistance groups, and slowly making their way back to Allied lines. The wartime setting is unusual for the series. The action is grimmer and the politics more immediately contemporary than in the African novels. Tarzan in his sixties is recognizably the same character but tempered by long experience. Burroughs wrote the book partly from his own observations as a war correspondent in the Pacific. A surprising and substantive late entry.