The pre-industrial humanoid inhabitants of the planet Neural, peaceful hunters and townsfolk who were pushed into an arms race when the Klingons secretly supplied one side with flintlock firearms.
The people of Neural appear in the Original Series episode A Private Little War. Kirk surveyed the planet thirteen years earlier as a young lieutenant and befriended Tyree, now leader of the Hill People. He remembered the natives as remarkably gentle, armed only with bows, and recommended that they be left alone.
Returning in 2268, he finds the Villagers shooting at the Hill People with flintlocks. Their leader Apella is being coached by the Klingon Krell, who introduces each improvement slowly so that it looks like local invention. The planet is also home to the mugato, a horned white ape with a venomous bite, and to the Kanutu, healers such as Tyree's ambitious wife Nona.
Nona steals Kirk's phaser and is killed by Villagers. The grieving Tyree asks for weapons, and Kirk, over McCoy's objections, arms the Hill People with matching flintlocks to keep a balance of power.