Sentinel Base was a facility located on a moon in a remote system of the Outer Rim's Arkanis sector. Along with the other Sentinel bases, its purpose was to protect the constuction of the Death Star battle station.
Sentinel Base was a prefabricated station, meant to be deployed via starship to its location on the Sentinel moon. Originally a cramped garrison base, it grew to become a large complex of interconnected domes and hangars, with additional modules either prefabricated or assembled onsite, as well as an adjacent landing field and deflector shield generator. Because of its importance, it was usually protected by a flotilla consisting of numerous capital ships as well as smaller vessels, including the frigate Salliche, the tug Fremond, and the Imperial-class Star Destroyer Core Envoy
A prefabricated garrison base, the original modules for Sentinel Base were deployed by a Victory-class Star Destroyer in 21 BBY, during the galactic conflict known as the Clone Wars. It was meant to supervise supply shipments to and otherwise safeguard the top-secret Galactic Republic project undergoing construction in nearby Geonosian space.
After the transition into the Galactic Empire, the base fell under the control of the Imperial Military, and continued to support the construction of the battle station, which had now evolved into the Death Star, well into the Empire's reign. Initially under the command of Vice Admiral Dodd Rancit, by 18 BBY he would be replaced by Moff Wilhuff Tarkin by order of Emperor Sheev Palpatine himself.
In 14 BBY, a group of rebels attacked the base with old Separatist technology, including a cobbled-together warship. Tarkin and his forces defeated them, however the capital ship escaped before it could be disabled.
- (Indirect mention only)