Sword and Planet Science Fiction

Sword and Planet Science Fiction merges the medieval with the cosmos. These are action filled stories of adventure taking place on distant planets and feature swords, ray guns, and interstellar travel. The emphasis is on swashbuckling adventures, a larger than life hero (usually with a sword), and usually some sort of princess to rescue. The actual real science behind the technology in a Sword and Planet is not well defined.

Generally, the protagonist is a hero-figure from Earth (an "Earthman"). Many of the battles fought by the protagonist are hand-to-hand combats, often featuring a sword. The sword is only one of many medieval aspects Sword and Planet features; often the alien worlds are described as more primitive, or medieval than Earth.

This characteristic creates anachronistic situations. For example, aliens possessing the technology to use space crafts, but domesticated animals are used for ground transportation. As such, Sword and Planet Sci Fi is more science-fantasy than science.

Sword and Planet vs. Planetary Romance

There is a lot of overlap between Sword and Planet and Planetary Romance to the point where some use them interchangeably, but they are not necessary the same. Planetary Romance tends to be more part of the Space Opera genre than Sword and Planet. As some have said, a more "realistic and grown up" version of Sword and Planet. Planetary Romance tends to be written in a more modern style and feature more reaslistic technology and maybe even the veneer of real science behind the ideas, yet still in the tradition of the Barsoom Books. Sword and Planet is heavily influenced by Burroughs' Barsoom Books (hero being the only Earthman, swords or other archaic weapons used to fight with, advanced technology on the alien planet combined with many medieval elements, etc).

Other similar genres would be Science Fantasy. Think of Sword and Planet as science fiction's version of fantasy's Sword and Sorcery subgenre.

You can view the crowd-ranked "Popular" Sword and Planet Books list and vote and/submit entries to it.

Other Features of Sword and Planet Science Fiction

Level of Real Science
None. Science is not the focus of Sword and Planet stories. Indeed, the science is more fantasy than reality. For example, there is little to no attention paid to how a human can live in an alien environment or how a human can be transported to an alien world.
Level of Grand Ideas/Social Implications
Low. These stories are focused on the action and the adventure, not on any grand ideas.
Level of Characterization
Low. Generally, the characters who appear in Sword and Planet Sci Fi are stock characters.
Level of Plot Complexity
Moderate. As an adventure story, Sword and Planet Sci Fi is plot driven. However, the stories of the Sword and Planet Sci Fi sub-genre tend to follow the same basic plot: a chivalrous man is transported from Earth to an alien planet, the Earthman discovers he is the lone human, the Earthman becomes involved in a conflict between two parties (two factions, nations, or species), he picks the side with the most beautiful woman, the woman is kidnapped, the man takes his sword and goes to rescue her and along the way fights off monsters and alien animals.
Level of Violence
High. Considering that there is a weapon in the title of this sub-genre, expect the heroes to be wielding swords, or ray guns, and battling bad guys.

Related Science Fiction subgenres

Pulp Science Fiction. Almost all Sword and Planet Sci Fi stories are part of the Pulp Sci Fi tradition, featuring high adventure storylines.
Sci Fi / Speculative Fiction. As there is usually not a high level of actual real science (or any attempt to break down the scientific rules present in the world into something real-world coherent), Sword and Planet might be referred to as Sci Fi or simply placed under the Speculative Fiction branch.
Science Fantasy. If fantasy elements such as magic are introduced to a Sword and Planet tale, you have a Science Fantasy. Think Star Wars with the Force Wielding, Lightsaber swinging Jedi. Science Fantasy is more of a general term that could include Sword and Planet.
Space Western. Some similar elements to Sword and Planet. Replace swords with guns and make the hero into a lone brooding protagonist, change the medieval to a wild west like world, and the setting an untamed wild landscape (somewhere in the universe) and you have a Space Western. Sword and Planet can contain elements of or be contained within the Space Western genre.
Planetary Romance. Very similar to Sword and Planet (often the two terms are used interchangeably). However, Planetary Romance refers to an adventure that occurs on another, usually exotic planet. The technology might not specifically be medieval (i.e. characters don't use swords, or some such) but more futuristic. As such, sword and planet might be a planetary romance while a planetary romance might not be a sword and planet tale.

Popular Sword and Planet Science Fiction Books

1 English Empire

By Poul Anderson. A sequence of novels that take English knights and make them rulers of alien worlds.
2 John Carter of Mars series

By Edgar Rice Burroughs. The prototype for the Sword and Planet sub-genre. Heroism and chivalry are found in all the adventures of this series that takes place Mars.
3 Almuric

By Robert E. Howard. The muscular hero of this novel is transported to the alien world Almuric and battles monsters.
4 The Pnume

By Jack Vance. The fourth in the Planet of Adventure sequence, this novel features hostile aliens and an Earthman who must survive.
5 The Sword of Rhiannon

By Leigh Brackett. An unlikely hero is plunged into Mars' past.
6 The Port of Peril

By Otis Adelbert Kline. One of several novels set on Venus that Kline wrote. This novel features a man whose wife has been kidnapped by a race of pirates.
7 Warrior of Llarn

By Gardner F. Fox The first of two novels, in this one the protagonist is whisked off the the alien world of Llarn and find himself in the body of the alien who called him there--swashbuckling ensues.
8 Gor

By John Norman. This series is about an Earthman who is transported to a counter-Earth called Gor, which is located on the other side of the sun. This series has become infamous for its portrayal of female sexual slavery.
9 Dire Planet trilogy

By Joel Jenkins. Dire is the hero of this trilogy; he travels to a barbaric past on Mars.
10 Dray Prescot

By Alan Burt Akersr. A sequence of some 53 novels and short stories featuring the protagonist Dray Prescot on the world of Kregen in the Antares star system, who is trained by an alien secret society.