Eol Sha existed as a volcanic planet located in the Corva sector of the Outer Rim, not far from the Cauldron Nebula. Despite possessing a relatively temperate climate, the planet was largely characterized by geological instability. Its surface was scattered with geysers and volcanoes, and it experienced frequent destructive natural events like avalanches and groundquakes.
During the era of the Galactic Republic, gas miners established a presence on the planet. Eol Sha was accompanied by a single moon, notable for its unstable and decaying orbit. By 9 ABY, when the planet was rediscovered, predictions indicated that the moon would collide with Eol Sha within a few years. The New Republic oversaw the evacuation of the planet's remaining inhabitants, who were then resettled on Dantooine in 11 ABY. Later in the same year, the Sun Crusher, an Imperial superweapon piloted by the renegade Jedi Kyp Durron, destroyed the Cauldron Nebula. This event almost certainly resulted in the annihilation of Eol Sha and its entire solar system.
Back in 89 BBY, a group of Human business people attempted to create a gas mining operation inside the Cauldron Nebula. They used ramjet mining ships to move through the nebula, gathering gases to be processed into rare elements and then sold. Eol Sha, being the only livable planet nearby, was settled by colonists who were supposed to help with the nebula's mining. However, the mining idea was flawed because the owners greatly underestimated how much it would cost to build and keep up the harvest ships. This, along with the rising costs of processing the mostly useless gases in the nebula, caused the owners to give up on the project, leaving the colonists on Eol Sha to survive on their own on the tough planet.
Over time, the people of Eol Sha got used to their new home, hunting bugdillos that looked like crustaceans and gathering edible lichens for food. At some point, a female Jedi named Ta'ania made the planet her home while raising her forbidden children. Gantoris was thought to be one of her descendants, as he also had a connection to the Force. Eventually, he became the leader of his people. After being cut off from the larger galaxy for years, the New Republic rediscovered the mining outpost in 9 ABY. Noting that the planet was geologically unstable and that the moon was about to crash into Eol Sha, the representative suggested that everyone be evacuated right away. But this report was ignored by government officials because the New Republic was busy fighting Grand Admiral Thrawn in a military campaign.
Two years later, in 11 ABY, Luke Skywalker went to the planet to find Ta'ania's children. When he met Gantoris and saw his Force abilities, Skywalker convinced him to join his effort to rebuild the Jedi Order by promising to move the planet's thirty-eight people to a better place. As a result, the New Republic moved the people of Eol Sha to Dantooine soon after Gantoris left with Skywalker. Sadly, everyone in the new colony was killed by AT-ATs during Admiral Daala's first attack on the New Republic.