Barsoom

Alex Raymond's strip began in 1934 as King Features' answer to Buck Rogers, and the template it reached for was Burroughs's:

• An Earthman stranded on an alien world who becomes its champion
• A princess of that world as the romantic centre
• Warring races, court intrigue and a tyrant, all settled by swordplay rather than by the advanced technology the setting obviously has

That last point is the signature of the form. Planetary romance keeps the sword in a world with airships, and Burroughs is where the convention comes from. Flash Gordon then carries it forward to Lucas, which the graph already holds.

Anne reacted against the traditional "Planetary Romance" framework popularized by books like A Princess of Mars. In those books, an Earthman crosses space, gets an enhanced body, and fights to save a helpless alien princess. Restoree hilariously mirrors this setup but flips the genders: an Earthwoman crosses space, gets a physically enhanced body, and has to use her brain to rescue a politically catatonic alien prince.

• Foundation : Barsoom was part of the pulp/planetary-romance tradition Lucas drew on when developing Star Wars. Most importantly, the earliest Journal of the Whills draft (which became Star Wars) directly parallels Burroughs's A Fighting Man of Mars.
• Genre : Barsoom helped establish the formula of science fiction + fantasy + swordplay + alien worlds + princesses + monsters + adventure that Star Wars adopted.
• Worldbuilding : Desert worlds, ancient civilizations, strange species, warrior cultures, exotic cities and a mixture of advanced technology with archaic societies are very Barsoomian.
• Narrative : The outsider hero entering an exotic planet, becoming a warrior, encountering alien cultures, rescuing/fighting for a princess, and participating in large-scale adventure are classic Barsoom patterns.

The 2012 Disney film John Carter is a direct live-action adaptation of A Princess of Mars, the first novel in Edgar Rice Burroughs' famous 11-book Barsoom series. The story is set on Barsoom, which is the native Martian name for the dying, war-torn red planet.

Gary Gygax lists it in Appendix N of the 1979 Advanced Dungeons & Dragons Dungeon Master's Guide, his published list of the fiction that shaped the game. Burroughs appears as "Pellucidar series; Mars series; Venus series". Barsoom's sword-and-planet adventure, a swordsman hero among alien races and ruined cities, is part of the pulp tradition the game drew its tone from.