Er'stacia was a temperate planet with a surface dominated by large tidal pools. The native Er'stacians divided themselves into clans based upon lineages traced back to the tidal pools of their ancestors. The clans all revered a single forebear known as the Venerable One, who was represented as a massive stone known as the Megalith. Despite this universal veneration for this object, however, each clan believed that it should have sole possession of the statue. This resulted in near-perpetual clan wars during which the Er'stacians wielded a mixture of low- and high-tech weaponry, such as swords, spears, and walkers.
At some point during the final decade of the Galactic Republic, one Er'stacian clan war had grown so out of hand that, when word of it reached the Jedi Council on Coruscant, the Jedi feared it might result in genocide. The council sent Jedi Master Mace Windu to negotiate a peace settlement. He decided that no peace was possible as long as the clans clung to the belief that only one of them could possess the Megalith, so he carved it into thousands of pieces, forcing the Er'stacians to either work together to repair it or to divvy up the rubble.
- The Complete Star Wars Encyclopedia