The Yinchorri are a race of tortoise-like humanoids native to the planet Yinchorr, and are known for their immunity to the manipulations of the Force. As a race, they were first admitted to the Old Republic shortly before the Battle of Naboo. The Yinchorri society was broken into the Intelligentsia and a warrior caste, and the Yinchorri were thought of as technophiles by the Old Republic.
The Yinchorri were quick to pick up and use any form of technology, including starships and weapons, and quickly learn how to subjugate their neighbors. They also discovered the usefulness of cortosis armor, when they leanred that it was capable of stopping a lightsaber. The Yinchorri developed a form of military transportation based on the wings of insects, with a powerpack which strapped to their backs and six thin wings for propulsion. Unfortunately for the Yinchorri, they were not exceptionally intelligent, and were drawn into the machinations of Darth Sidious, who used their aggressiveness to begin attacking Republic outposts and, later, the Jedi Knights themselves. After an attack on Mayvitch 7, the Jedi Knights were called in to put an end to the so-called Yinchorri Uprising. Only after taking many losses were the Jedi able to quell the Yinchorri by destroying their base on Uhanayih and forcing the Yinchorri to surrender.
After the rise of Emperor Palpatine, the Yinchorri were nearly wiped from the planet during the Imperial retaliation for their rebellion. The Empire then established a training facility on Yinchorr for the Royal Imperial Guards. Unknown to the Empire, several small clusters of Yinchorri managed to survive their extermination. In the wake of the Battle of Endor, they took control of the former Imperial training facility and used it as their governmental seat of power. They chose to remain independent from the New Republic.