Exodite

The Exodites are civilian Eldar who are not aligned with the Craftworlds or the Dark Eldar. They're basically Amish dinosaur-cowboy space elves.

The Exodites originated from those citizens of the Eldar Empire who saw the corruption festering in the souls of the Eldar and decided they needed to purify themselves. To do so, they left the Empire and its conveniences for worlds on the edge of the galaxy (an exodus, hence "Exodites"), where they would be forced to work hard just to survive. This kept them focused and busy, and prevented them from being lost in hedonism like their relatives back home. When the Empire's increasing debauchery gave rise to Slaanesh, the Exodites survived because they were far from the center of the Empire (what would later be called the Eye of Terror) and because their hard lifestyle and self-denial meant that Slaanesh had little purchase on their souls. Apparently, they are not completely free of Slaanesh's influence; when they die, their souls are stored and contained in their planet's World Spirit (analogous to the Infinity Circuit of the Craftworlds).

As of the 41st Millennium, the Exodites still keep to themselves, though the expansion of the Imperium of Man and the encroaching Tyranid Hive Fleets have brought them into conflict. They defend themselves with their dinosaur-riders, and Craftworld Biel-tan often dispatches forces to aid Exodites under attack.