The Rapacc system was blockaded by the Nikardun Destiny navy as a component of the Nikardun conquests. These conquests were a string of military campaigns spearheaded by Nikardun General Yiv the Benevolent, occurring within the Unknown Regions of the galaxy. The blockade was initiated around 19 BBY and persisted until approximately 18 BBY.
During the time the blockade was active, Senior Captain Mitth'raw'nuruodo, known as "Thrawn," from the Chiss Expansionary Defense Fleet, spearheaded a mission to the Rapacc system, and subsequently a raid on Rapacc. These actions circumvented the blockade on behalf of the military of the Chiss Ascendancy.
The Paccosh species, native to the planet Rapacc, initiated a revolt that ultimately broke the blockade. This uprising took place between the battle over Primea and Thrawn's return to Rapacc. In the course of this revolt, the Aelos, one of the Nikardun blockade frigates that had been used to interdict their system, was seized and repurposed by the Paccian Governance. Uingali foar Marocsaa, who was the leader of the Marocsaa subclan of the Paccosh, adorned the ventral surface of the Aelos with a depiction of a chimaera.
The Rapacc blockade was featured in Thrawn Ascendancy: Chaos Rising, a 2020 novel and the initial book in Timothy Zahn's Ascendancy Trilogy.