Thuvia, Maid of Mars is a science fantasy novel by American writer Edgar Rice Burroughs, the fourth of the Barsoom series.

The principal characters are Carthoris (the son of John Carter of Mars) and Thuvia of Ptarth, each of whom appeared in the previous two novels.

Helium and Ptarth are both prominent Barsoomian city state/empires, and both Carthoris and Thuvia were secondary characters in the previous two novels.

As Thuvia suffers the common Burroughsian heroine's fate of being kidnapped and in need of rescue, Carthoris' goal is abetted by circumstances.

Burroughs began writing Thuvia, Maid of Mars, in April 1914, at the time describing it as a 'Carthoris' story.

After a break in California, he had begun a furious writing schedule, including other works as well as what was to become Thuvia, Maid of Mars.

[3] Burroughs reached New York on June 23, and several days later mailed the finished typescript of what was still entitled "Carthoris", describing it as "another Martian story" he wished "to sell for use in All-Story Cavalier Weekly".

[5] Most of the action in a planetary romance is on the surface of an alien world, usually includes sword fighting, monsters, supernatural elements as telepathy rather than magic, and involves civilizations echoing those on Earth in pre-technological eras, particularly composed of kingdoms or theocratic nations.

[4] Burroughs' vision of Mars was loosely inspired by astronomical speculation of the time, especially that of Percival Lowell, who saw the planet as a formerly Earthlike world now becoming less hospitable to life due to its advanced age,[11] whose inhabitants had built canals to bring water from the polar caps to irrigate the remaining arable land.

[14] Barsoomians distribute scarce water supplies via a worldwide system of canals, controlled by quarreling city-states.

[17] Thuvia, Maid of Mars is notable in that John Carter's son, Carthoris, invents an apparent precursor of the autopilot (decades before an actual device was perfected).

[18] They had been fleeing from the attacks of Green Martians, during which most of them were killed (including all women and children), when they found a defensible location and came to a dramatic realization that the mind is everything, and hence developed advanced telepathic powers including the ability to create phantom bowmen to combat their Green Martian adversaries.

Such is the detail of their power of imagination that the bowmen even appear to die in combat, and the Green Martians are killed by their arrows.