Umbara, known as the "Shadow World" due to the lack of sunlight on its surface, was a planet located within the Expansion Region. The planet was also an exporter of doonium, a metal utilized in the construction of starships. During the Clone Wars, the planet was initially part of the Galactic Republic before seceding to join the Confederacy of Independent Systems. It proceeded to host one of the larger battles of the Clone Wars and eventually fell to the Republic. After the fall of the Republic, the planet fell under the power of the Galactic Empire. During the Imperial Era, Captain Thrawn suppressed an uprising on Umbara that had been engineered by the shadowy insurgent leader Nevil Cygni.
Umbara was a planet in the Expansion Region that experienced no sunlight on its surface, earning it the name "Shadow World." Situated within the occluding Ghost Nebula sector, Umbara was cut off from the rest of the galaxy. This resulted in the development of advanced technologies that far exceeded the galactic standard by the native Umbarans.
Umbara sported a variety of predatory animal and plant life. The plant life on Umbara was particularly aggressive, and bioluminescence was a common trait, found in both Zabrak Spines and death's embrace. Umbara also had large doonium reserves, which led to the emergence of a substantial mining and refining sector in its economy. The planet was also known to have several moons including an outermost one.
Umbaran soldiers during the Battle of Umbara.
The Umbarans had been members of the Galactic Republic since the government's founding, but, despite their long history of taking part in the galaxy's politics, they always prioritized their homeworld over the galactic government. The Sith-obsessed Umbaran Sly Moore lived on Umbara until she was kidnapped by the Sith apprentice Darth Maul, who brought her to the Cron Drift asteroid field. She would ultimately become an ally to the Sith Order she was so fascinated by. Despite their past of prioritizing Umbara and its people's reputation of being deceitful and employing self-serving schemes, Umbara displayed faultless loyalty to the Republic during the Separatist Crisis, a time of political crisis where thousands of star systems seceded from the Republic and joined Count Dooku's Confederacy of Independent Systems. When the Clone Wars broke out between the Republic and Separatists, Umbara remained a staunchly loyalist world.
Umbara was represented by Senator Mee Deechi in the Galactic Senate of the Republic, who aggressively supported for increased military spending. However, following Senator Deechi's assassination, Umbara defected to the Confederacy. In response, the Grand Army of the Republic would launch an invasion of the Shadow People's homeworld. Jedi Generals Obi-Wan Kenobi, Saesee Tiin, Anakin Skywalker, and Pong Krell led the assault with the 501st Legion and the 212th Attack Battalion. During the fighting, the clones battled against the might of the Umbaran's advanced military technology, struggling to combat their mobile heavy cannons, Impeding Assault Tanks, Umbaran hover tanks, and Zenuas 33 Umbaran starfighters.
Clone troopers Jesse, Tup, and Dogma during the battle.
Shortly after landing, Anakin Skywalker was called back to Coruscant at the request of Supreme Chancellor Palpatine. Krell assumed command of the 501st in Anakin's absence. The Umbaran's unique and powerful weaponry and militia made the fighting long and costly for the clones on the planet's surface while battles continued in the skies between the Republic and Separatist fleets. As the fighting progressed, men of the 501st noted and began to grow sour with Krell's casualty-heavy tactics despite their successful results. Shortly after capturing an Umbaran airbase, Krell ordered the execution of clone troopers CT-5555 "Fives" and CT-5597 "Jesse," who had hatched their own plan to take out a Separatist supply ship. Later, Krell betrayed the 501st Legion by telling them that the soldiers of the 212th Attack Battalion were actually Umbarans disguised as clone troopers, and Clone Captain CT-7567 "Rex" realized Krell was working for the Separatists. Led by Rex, the 501st and 212th united to take down Krell, who was stunned by clone trooper CT-5385 "Tup" and taken into custody. CT-6922 "Dogma," feeling betrayed, killed Krell when Rex began to interrogate him and was himself taken into custody. Republic forces soon reclaimed Umbara.
During the early months of the Imperial Era in 19 BBY, the Galactic Empire dealt with surviving pockets of resistance, including on Umbara. Eventually faced with a debt it had no way to pay to the Empire, Umbara was one of many worlds that surrendered its remaining independence, fully placing the planet under the power of the Empire.
The pirate and insurgent leader Nightswan instigated an uprising on Umbara in order to facilitate the Imperial takeover of Umbara's mining and refining sector. Nightswan thought it would be easier to bribe the Imperial inspectors rather than their Umbaran counterparts. Despite resistance from leftover Separatist forces, namely, vulture droids, Captain Thrawn helped secure an Imperial victory by convincing Commander Alfren Cheno, who was part of the task force, to bombard a ground-based transmitter on Umbara's outermost moon despite Admiral Carlou Gendling's orders not to. Gendling was furious with Thrawn, and Cheno eventually retired due to the incident.
At one point during the Imperial Era, a new pocket of doonium was discovered on Umbara. With the Empire in constant need of new raw materials for its construction projects, the Mining Guild was ruthless in its exploitation of the doonium deposit, and Umbara was one of several planets to suffer such a fate.
Umbaran Society was ruled by a council consisting of members from a royal caste called the Rootai. Ordinary Umbarans could rise up through many of these social castes by spying, subterfuge and assassination. The Umbarans were with the Galactic Republic for centuries prior to joining the Confederacy of Independent Systems and were considered to be suspicious. Notable Umbarans included Sly Moore who replaced Sei Taria as Palpatine's Chief Administrative Aide, Mee Deechi who was the Senator representing Umbara in the Galactic Senate prior to his death and Sorc Tormo who was a crime lord that led the Haxion Brood during the Imperial Era. The Umbaran Jedi Master and Wayseeker Orla Jareni operated during the High Republic Era before dying in 230 BBY during the Destruction of Starlight Beacon.
Due to their isolation from the rest of the galaxy, the Umbarans achieved great technological advances, in technologies such as military technology. Among these breakthroughs was a gas that stimulated soldiers to fight longer and harder, the creation of sophisticated military vehicles utilized by the Umbaran Militia, and the introduction of advanced blaster pistols. Non-Umbarans found that it was very difficult to use their technology. Umbarans also spoke their own native language called Umbarese.
Traditional Garments such as the Umbaran shadow cloak were worn by Umbarans. Umbaran glass was a type of glass, with Greez Dritus using it to cover a terrarium aboard the Stinger Mantis.