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After seeing this post – The Covers of Jungle Stories — Through the Shattered Lens; original post – The Covers of Jungle Stories — Through the Shattered Lens, I decided to look up Ki-Gor in different places. Turns out Ki-Gor was most likely the longest lasting knock-off of Tarzan – http://www.howardandrewjones.com/heroic-fiction/pulp/the-mighty-ki-gor-tarzans-forgotten-rival.
It’s worth noting Ki-Gor as originally published is most likely in the public domain unless the copyright was renewed. Any re-makes that add to the original stories or add new artwork would have those parts covered under copyright. Best to check with the Copyright Office to verify if a particular story is public domain or is under copyright protection. It looks like at least one company is doing re-makes.
A few other articles on Ki-Gor:
https://www.amazon.com/Ki-Gor-Complete-John-Peter-Drummond/dp/1448618207 (not an affiliate link)
Drummond, John Peter ( - ) Pseudonyms: House Name AU,Ki-Gor - Tigress of T'wanbi AU,Ki-Gor - The Nirvana of the Seven Voodoos AU,Ki-Gor - The Bride of the Serpent God Ki-Gor - Voodoo Slaves For The Devil's Daughter Ki-Gor - Death Seeks For Congo Treasure Ki-Gor - The Monsters Of Voodoo Isle Ki-Gor - Night Of The Wasuli Death Ki-Gor - Slave-Caverns Of Molundu Ki-Gor - Ki-Gor - King Of The Jungle Ki-Gor - Ki-Gor and the Stolen Empire Ki-Gor - Ki-Gor and the Secret Legions of Simba Ki-Gor - Ki-Gor and the Forbidden Mountain Ki-Gor - Ki-Gor and the Cannibal Kingdom Ki-Gor - Paradise That Time Forgot, The Ki-Gor - The Empire of Doom Ki-Gor - Lair of the Beast Ki-Gor - The Temple of the Moon God Ki-Gor - White Savage Ki-Gor - Slaves For the Renegade Sultan Ki-Gor - Blood Priestess of Vig'Na Ki-Gor - The Cannibal Horde Ki-Gor - The Devil's Death Trap Ki-Gor - Eyrie of the Golden Goddess Ki-Gor - Caravan of Terror Ki-Gor - Death Krall of the Elephants Ki-Gor - Stalkers of the Dawn World Ki-Gor - Cobra Queen of the Congo Legions Ki-Gor - Monkey-Men of Loba-Gola Ki-Gor - Land of the Lost Safaris Ki-Gor - Silver Witch Ki-Gor - Huntress of the Hell Pack Ki-Gor - The Golden Beasts of Zuli'Maen Ki-Gor - Slave Brides For the Dawn Men Ki-Gor - Safari For Black Ivory Ki-Gor - Blood Gold of B'Tonga Ki-Gor - Where Man-Beasts Prowl Ki-Gor - Warrior Queen of Attila's Lost Legion Ki-Gor - The Diamond Fangs of M'Buba M'N Ki-Gor - The Seven Silver Skulls of L'Gonda Ki-Gor - Slave of the Jackal Priestess Ki-Gor - Cromba Has a Thousand Spears Ki-Gor - The Golden Claws of Raa Ki-Gor - The Lost Beast of Ta-Tamba Ki-Gor - Safari of the Serpent Slaves Ki-Gor - The Mad Monster of Mu'ungu Ki-Gor - The Sword of Sheba Ki-Gor - Lost Priestess of the Nile Ki-Gor - The Beast Gods of Atlantis Ki-Gor - Flame Priestess of Carthage Ki-Gor - Silver Caverns of Molundu Ki-Gor - Fane of the Python Princess Ki-Gor - White Cannibal Ki-Gor - The Giant Gorilla Men