Malastare Narrows, situated on the planet of Malastare, was found within the Mid Rim Territories. In 34 BBY, before the outbreak of the Clone Wars between the Galactic Republic and the Confederacy of Independent Systems, a fleet belonging to the Corporate Alliance and commanded by Admiral Trench, a Harch, had established a blockade surrounding Malastare.
Subsequently, the Republic dispatched a fleet of starships with the goal of dismantling Trench's blockade and obliterating his fleet; however, they were repelled on multiple times, enduring substantial losses. The situation was later resolved when a task force under the leadership of Jedi Master Kep-She successfully destroyed Trench's flagship. This outcome led to assumptions of the Harch's death, even by Jedi Knight Anakin Skywalker. Nevertheless, Trench was later discovered to have survived this battle, as he spearheaded a Separatist blockade during the Battle of Christophsis in 22 BBY amidst the Clone Wars.
The initial mention of Malastare Narrows occurred in "Cat and Mouse," which was the sixteenth episode in the second season of Star Wars: The Clone Wars. This episode was broadcast on March 26, 2010.