During the early months of the Imperial Era, a resistance against the Galactic Empire emerged on the Expansion Region planet Umbara, which had been a major supporter of the Confederacy of Independent Systems during the Clone Wars between the Confederacy and the Empire's predecessor, the Galactic Republic. In 19 BBY, the resistance put up a heavy martial opposition to the Imperial Military.
Lieutenant Commander Orson Callan Krennic told the Erso family of researchers that the Empire considered the Umbara rebellion an outgrowth of the Clone Wars. Krennic also claimed the Empire's response to the rebellion, along with other resistance groups appearing at the same time, was merely a pacification operation. Despite the resistance's struggle for Umbara, the planet eventually fell under Imperial control.
The Umbara resistance was mentioned in the 2016 novel Catalyst: A Rogue One Novel, by James Luceno.
The Umbara resistance was mentioned in the 2016 novel Catalyst: A Rogue One Novel, by James Luceno.