John Carter of Mars was a comic-book serial adaptation of the Martian novels written by Paul S. Newman and drawn by Jesse Marsh. First published by Dell Comics in 1952, the series was released under several different imprints (Four Colors, and Gold Key; Gold Key printed the comics out of order). Later it was republished by Dark Horse as "John Carter, the Jesse Marsh Years".
This creature sheet from the comic, designed to inform the readers, is a fascinating early interpretation of the strange inhabitants of Barsoom. Creature design has come a long ways since then.
Dell's adaptation mostly followed the original books in terms of plot, but the art deviated considerably from what was described in the books. For one thing, John Carter was no longer a former Confederate soldier; now he was a US Army soldier fighting in Korea. Also, he and his Martian allies were all trapped in "strange, unsightly pieces of cloth" - comics were still considered a medium for children, and so the scant sword-and-planet dress code was traded in for attire that appeared to have been lifted from Krypton. Additionally, Marsh portrayed the Black Pirates not as warriors with jet-black skin but as vaguely Asian or Russian-looking men in black costumes, with a helpful Jolly Roger emblem across the chest to inform the reader of their profession. The Therns became Germanic, and the Okarians became cousins to the Black Pirates, and thus also ambiguously Russian or Asian. (-from the Encyclopedia Barsoomia)