John Carter of Mars

John Carter of Mars was published in 1964, fourteen years after Burroughs's death, as a posthumous omnibus collecting two short novels his estate had published separately. The book is the eleventh and final volume in the canonical Barsoom sequence and is the shortest of all of them. Reader appetite for new Barsoom material in the 1960s was strong enough that the estate was willing to release whatever was left.

The first of the two novels collected here is John Carter and the Giant of Mars, originally a 1940 children's adventure that Burroughs had ghost-written or co-written with his son. The text is simpler and less politically detailed than the main canon, and its inclusion is sometimes considered apocryphal. The second, Skeleton Men of Jupiter, originally appeared in 1942 as a novella in Amazing Stories and is more cohesive with the rest of Barsoom. The book functions essentially as a memorial volume, gathering loose ends. For Barsoom completists rather than first-time readers.