The Enkarans were a tribe of humanoid aliens that SG-1 helped return to their ancestors' home world after they were freed from slavery under the Goa'uld. The original Enkaran home world had no Stargate. It was believed that the Goa'uld took a group of Enkarans from their world in spaceships long ago.
The Enkarans were humanoid, but their unique physiology made them extremely sensitive to specific atmospheric conditions. Without the exact environmental conditions the Enkarans went blind and eventually died. Their physiology was adapted to an extremely rare atmosphere which allowed them to thrive.
Stargate Command discovered the situation they were in and searched for weeks for a suitable planet to resettle them. Eventually they were successful, and the Enkarans immediately took root in their new world, establishing structures and giving thanks to SG-1 for saving them. But only weeks after the new settlements were rooted, a threat from nearby began rumbling through the forests of the beautiful world; an alien ship apparently intent on terraforming the entire surface of the planet.
Negotiations with Lotan, the life form created by the advanced Gadmeer ship to communicate with the Enkarans, failed at first, resulting in a threat which would wipe out the Enkaran tribes. But with the aid of Daniel Jackson, Lotan discovered the location of the original Enkaran home world in the ship's memory banks, and agreed to return them. The Enkarans were more than pleased to return to their people. (SG1: "Scorched Earth")