The Ancient Order of Pessimists comprised a group of reclusive religious individuals residing on Maryx Minor, adhering to a pessimistic philosophy and way of life. While evading Boba Fett and Darth Vader, Abal Karda sought refuge within their secluded hermitage. Soon after, Fett infiltrated the hermitage, fatally wounded Karda, and seized the container holding the disembodied, yet animate, head of Selestrine. Vader then appeared and engaged Fett in combat for the box. After securing the box, Vader made his way back to his Imperial-class Star Destroyer. Having lived through the confrontation between Fett and Vader, the High Hermit underwent a profound realization, embracing optimism. However, Vader ordered the complete annihilation of the hermitage from space, ensuring the hermits' silence regarding the witnessed events.

The Ancient Order's members held the belief that existence was at its absolute worst. They tended to emphasize the negative aspects of life, focusing on unfavorable conditions and anticipating the most disastrous outcomes in every scenario. Although they believed their life of dread would only end with their demise, the hermits of the Ancient Order did not intentionally seek death. They regarded every misfortune as a burden that must be endured without complaint. While generally pacifistic, they occasionally resorted to violence to defend themselves from those who disrespected their beliefs. While minor instances of optimism were tolerated, actively promoting complete optimism was deemed heretical and believed to invite further calamities upon the community.
The brothers, all male Humans, wore simple light gray robes paired with matching sandals. The community's leader, known as the High Hermit, was distinguished by his unique headwear, a robe adorned with blue markings, and a necklace. The daily routine at the hermitage was marked by the sound of a bell struck with a padded mallet. Each morning, the brothers of the Ancient Order employed bones in a casting ritual to foresee the future. Consistent with their pessimistic doctrine, the resulting omens were invariably grim, sometimes even more so than usual. Upon the death of a brother, the others conducted a funeral procession, casting his body into a fiery lava pit.

The Ancient Order of Pessimists was present as early as 3 BBY, during the lead-up to the Galactic Civil War, although its name suggested a much earlier origin. In that year, the hermits provided sanctuary to Abal Karda, a colonel in the Galactic Empire who was being pursued by the bounty hunter Boba Fett. Without the monks' knowledge, the colonel was in possession of a casket containing the living, speaking head of Queen Selestrine of the Icarii, who continuously prophesied his demise at the hands of Fett. In a fit of anger, Karda murdered one of the brothers, Mabob, accusing him of spying at his cell door. Eventually, Fett discovered Karda's hiding place, and the brothers of the Ancient Order found themselves caught in the conflict between the two men. Just when the situation seemed dire enough, the Supreme Commander of the Empire, Darth Vader, arrived at the hermitage and began battling Fett for Selestrine's head. By the end of their struggle, six brothers had perished, and several others were injured. As a result of surviving these dramatic events, the High Hermit experienced an epiphany and attempted to convert his brethren to a new optimistic outlook. However, the hermits had inadvertently sealed their doom by witnessing the confrontation between Fett and Vader. To guarantee their silence regarding the events that transpired on Maryx Minor that day, the Supreme Commander ordered the hermitage's destruction via orbital bombardment.
Despite the order's downfall, certain aspects of its teachings endured and attracted followers. Moff Foga Brill, an Imperial Warlord and leader of the Constitutional Protectorate of Prakith, encountered the Order's doctrines sometime after its destruction and secretly became a devotee during his tenure as governor of the hellish Deep Core world of Prakith. He later converted to the Church of the Dark Side upon the recommendation of his friend, Grand Admiral Peccati Syn.
The order's hermitage was situated near a geyser field in the mountains of Maryx Minor, a volcanic planet located in the Outer Rim region of the galaxy. A few years following the hermitage's destruction, the order had gained at least one adherent on Prakith.