The Tarasins were a sentient, reptilian species with two legs, originally from Cularin. They shared a distant ancestry with the massive Kilassin.

These reptilian beings, the Tarasins, typically stood between 1.6 and 1.7 meters tall. Their bodies were covered by translucent scales, which allowed the shifting colors of their skin underneath to be visible. A notable feature was a vibrant fan of flesh and scales, referred to as a kampo, that would flare open around their heads when they experienced intense emotions, potentially hindering negotiations due to the difficulty in concealing discomfort. This color-changing adaptation served for both camouflage and communication, and the scales possessed natural heat-repelling properties. For instance, they might display a brown hue when relaxed and in a comfortable setting, or turn red after prolonged exertion or when agitated. Furthermore, Tarasins possessed short tails and small spines, known as a sa'tosin, extending from their forearms, which enabled them to sense the presence of the Force. They were naturally inquisitive and protective, yet slow to anger. While not physically imposing, they possessed exceptional intelligence.
Initially, the Tarasins existed as nomadic tribes. However, at some point in their history, they chose to establish a different societal structure. Subsequently, Tarasins lived in a tribal organization within the jungle undergrowth of Cularin, forming groups known as irstat. While most irstat comprised several dozen individuals, some were significantly larger. For example, the Hiironi irstat had a population of approximately three hundred in 33 BBY. Conversely, the "alien" cities of Gadrin and Hedrett had a Tarasin minority population of 2,000 and 2,900 respectively, always below 15% of their total population.
The first two irstat that were established converged at a rock designated as a landmark. Each tribe would maintain its separation from the other, ensuring adequate food resources for both, while remaining within a day's travel distance in case of need. The rock served as the central point between them.
The structures within an irstat were constructed from wood, appearing easily dismantled and relocated to outsiders. However, the Tarasin were not typically nomadic. Some irstats began incorporating prefabricated buildings into their villages, though they were designed to blend seamlessly with the surrounding environment.
The eldest female of each tribe held the revered title of "Mother," considered an embodiment of perfection. She functioned as the spiritual leader of the irstat. The second eldest female assumed the role of chief, known as the Irstat-Kes. This arrangement, where females were not considered superior, was viewed as practical since the males were often away from the irstat, engaged in gathering food and other resources.
Over time, the rock that marked the meeting point of the first two irstats evolved into a monument within the Sacred ch'hala tree grove, encircled by numerous ch'hala trees. It was not used for worship, but rather to celebrate the forest life, and access was restricted to outsiders without a Tarasin escort. The irstat-kes of each tribe were expected to convene with their counterparts in the grove, and every Tarasin religious leader was required to visit the grove at least once, bringing a ch'hala sprout to plant in their respective irstat.
Tarasins were generally vegetarians, although they hunted kilassin for purposes other than food, such as for their hides or medicinal properties, as they found hunting kilassin for sustenance distasteful. Those residing near non-native settlements might adopt the practice of eating meat, but only in the presence of offworlders, and never kilassin meat.
The Tarasins' inherent curiosity fueled their desire to learn about the wider galaxy, and many frequently embarked on adventures beyond Cularin, though they preferred not to remain away for extended periods. These traits also fostered an openness to the customs and traditions of outsiders.

This receptiveness led them to readily trust the first offworlders who arrived on Cularin. While initial collaboration between the Tarasin and outsiders was productive, the offworlders soon sought to exploit Cularin's resources using methods that would cause lasting damage, prompting resistance from the Tarasin. The ensuing Tarasin Revolt (161 BBY–154 BBY) concluded with the Cularin Compact. This agreement granted certain rights to the Tarasins and prevented the unchecked exploitation of the planet's natural resources by outsiders.
During the revolt, some Tarasins sought refuge in the Ishkik caverns, where they discovered the local stone. Subsequently, they returned to their irstat way of life but began utilizing the ishkik stones for crafting tools or as decorative elements.
In 119 BBY, the Jedi Order established an experimental academy on the nearby planet Almas. Soon after, Tarasins began sending their Force-sensitive children to the academy. Master Nerra Ziveri accepted applications from students who might have been considered too old in other Jedi academies, particularly among Tarasins, but always carefully screened each applicant to mitigate potential risks. Elder Tarasins expressed concern that their younglings might find the non-irstat environment too daunting, potentially hindering their Jedi training. Consequently, elder Tarasins discouraged young ones from attending, but this proved ineffective. Moreover, Master Ziveri implemented new policies to adapt the Academy to the needs of Tarasin students (such as the Jedi quests to address the unease of Tarasins to leave their planetary system), and even constructed new buildings more suitable for them. The Elders eventually dispatched a Tarasin religious leader and Force adept, Mother Missira, to the Almas Academy, where she was tasked with overseeing the Tarasin students and imparting their cultural heritage. The Almas Academy subsequently became the alma mater of numerous Tarasin Jedi, some of whom ventured beyond the system as Jedi Knights.
Between 78 BBY and 53 BBY, some Tarasins were abducted by local crime lord Riboga the Hutt, with the intention of selling them off-system as slaves; however, Riboga primarily dealt with slaves from the Core Worlds. This practice ceased when Riboga was replaced by crime lord Nirama, who opposed slavery.
In 34 BBY, a Tarasin male named Duus departed from the planet Cularin. Despite a thorough search, the investigation was eventually abandoned, and Duus was declared a traitor to the Tarasin. Other Tarasins, such as Ta'Sen, also left Cularin but were not persecuted for reasons that remain unclear.
Tarasins communicated in Tarasinese, but they were also known to convey messages by simply altering their skin colors when spoken conversation was impractical, dangerous, or impossible. With time, an outsider could learn to interpret these nonverbal communications.
The Tarasin held the belief that they shared a symbiotic relationship with Cularin, and their religious beliefs centered around the reverence for the natural world. This profound connection to their homeworld contributed to their reluctance to leave it for extended periods. The Tarasin possessed a strong affinity for the Force, and their spiritual leaders often demonstrated the ability to harness the Force in subtle ways. With the establishment of the Almas Academy, numerous Tarasin pursued studies there to become Jedi.
The Tarasin regarded the ch'hala tree as sacred. This reverence may have stemmed from the trees' ability to shift their colors, similar to the Tarasin, but also from the tree's uniqueness on Cularin. As part of the Cularin Compact, the Tarasin permitted the harvesting of a limited number of these trees each year, but only for live transplants.