Umbarans resided on the dark world of Umbara deep within the Ghost Nebula. Umbarans could see in ultraviolet (below 300 nanometers) and had the ability to read, subtly influence and sometimes control the will of others.
Umbarans spoke the language Umbarese. Umbarans were gaunt, frighteningly pale Near-Humans with sunken eyes and cold calculating stares, due to the planet Umbara having an eternal twilight. Their eyes were well adjusted to the dark, but they were easily disoriented when exposed to bright sudden flashes of light.
Umbarans were highly secretive and manipulative creatures, who craved little else than power and influence. Many had a darker sense of humor than the average Human, which would manifest in social interactions. Masters of misdirection, these creatures almost never revealed their true thoughts or intentions.
Umbaran society was built on a finely detailed caste system comprising almost one hundred levels. Only those in the top ten caste levels were given the opportunity to leave their homeworld, explaining their rarity outside the Ghost Nebula. The primary ambition of the average Umbaran was to ascend through the caste levels, using tactics from blackmail and subterfuge to cool assassination, thus priming them for a life in politics. Failed plots to ascend the ranks of society were met harshly with the attempted perpetrator imprisoned and their family dropped to one of the lower caste levels. Dependent upon the rank of the targeted individual, the perpetrator risked a death sentence for themselves and their entire family. Successful maneuvering however, is rewarded with prestige, making it worth the risk. They could also tell if a person is lying due to their more sensitive eyes and their ability to sense heat.
The highest caste level, known as Rootai, comprised a council that ruled Umbara, and its members were considered royalty.
Umbarans have had a presence in galactic affairs since the dawn of the Galactic Republic, although few in number, they have always been at the forefront. During the time of the Galactic Republic, they strode eerily through the halls of power. Respected, yet feared for their ability to subtly sway others, Umbaran senators rarely had anyone foolish enough to call them an enemy.
It was a fallen Umbaran Jedi by the name of Phanius that touched off the first in a series of conflicts that eventually came to be known as the New Sith Wars. Nearly a millennium later, the Umbarans allied with the Brotherhood of Darkness against the Republic. An academy to train Sith assassins was opened on Umbara. Umbaran shadow spies served the Sith on planets such as Ruusan.
During the Rise of the Empire, Umbarans used their natural mental sway to secure positions of power. Supreme Chancellor Palpatine selected an Umbaran by the name of Sly Moore to be his Staff Aide. Moore was entrusted with some of the soon-to-be Emperor's darker secrets.
The death of the Emperor at the Battle of Endor caught many Umbarans by surprise. Fearing retribution from both the Imperial Remnant and the New Republic, the Umbarans fled civilized space back to the Ghost Nebula.
Umbra is Latin for "shadow."