The Umbarans are a race of outwardly humanoids native to the planet Umbara, and are known to have existed at the formation of the Old Republic. Umbarans are characterized by their pale, bluish skin and white-pigmented eyes. They are capable of seeing into the ultraviolet spectra of light, but have little vision in the normal, visible spectrum. In fact, an Umbaran can be momentarily blinded by a bright flash of normal light.
It has been said that Umbarans have the ability to subtly influence and control other beings, and it is known that many Umbarans used their strange abilities in identifying hidden Jedi during Emperor Palpatine's Jedi Purge. Because a great many Umbarans used their influence to secure positions of power within the government of Emperor Palpatine, as a people they feared that some form of retaliation might occur when Palpatine was killed at the Battle of Endor. This led the Umbarans to flee deeper into the Ghost Nebula, although they maintained an invisible information network to monitor the activities of the New Republic.
As a people, the Umbarans exist in a detailed caste system of nearly 100 distinct levels. Of these levels, only those Umbarans who are in the top ten are allowed to leave their homeworld and visit the galaxy at large. However, movement between caste levels is possible for all Umbarans, and most individuals spend a large portion of their lives planning how to move up to the next level. Those individual Umbarans who fail in an attempt to move upward, especially those who arrange for assassinations or other illegal activities, are usually sentenced to life in prison or death, depending on the caste level of the individual they tried to eliminate. This penalty is often made more severe by placing the individual's entire family under the same penalty, in an effort to prevent unnecessary deaths. Many Umbarans believe that the risks associated with moving up are far outweighed by the potential rewards, thereby perpetuating the practice.