The Lothal sector fleet, a component of the Imperial Navy, functioned as the designated sector fleet for the Lothal sector and was under the command of Admiral Kassius Konstantine. Its attempts to suppress regional insurgent groups, such as the Spectres and later the Phoenix Cell, proved unsuccessful. This ineffectiveness eventually led to the fleet being reinforced by the 7th Fleet commanded by Grand Admiral Thrawn. The fleet itself was a fleet.
Admiral Kassius Konstantine was in command of the sector fleet assigned to the Lothal sector. Primarily designed as a small task force to combat smuggling, the fleet consisted of, at a minimum, six Imperial I-class Star Destroyers, with the Relentless serving as its flagship. Furthermore, it incorporated at least two Arquitens-class command cruisers and operated in conjunction with Delta Squadron.
During the early rebellion against the Galactic Empire, Konstantine's fleet had the mission of suppressing rebel activities around the planet of Lothal. As part of these efforts, the fleet collaborated with the Inquisitorius, due to suspicions that certain local rebels possessed Force-sensitive abilities. In 2 BBY, the governor of the Lothal sector, Arihnda Pryce, expressed dissatisfaction with the fleet's limited success in combating a group of insurgents within her sector. Consequently, she requested the assistance of the Seventh Fleet, under the leadership of Grand Admiral Thrawn, to address the rebel threat. Following Thrawn's involvement in the campaign against the rebels, Konstantine then served under Thrawn's command, albeit tentatively.