Herdessa was a celestial body that existed within the Mid Rim region, specifically along the well-known Corellian Run hyperroute. During the Clone Wars, the Galactic Republic established a blockade around it. The Senator representing this astronomical feature in both the Republic Senate and later the Imperial Senate was Shea Sadashassa. A soldier named Vryant of the Imperial Army spent six years stationed on Herdessa. Following the dissolution of the Imperial Senate in 0 BBY, Sadashassa, along with numerous other senators, found themselves imprisoned within the Arrth-Eno Prison Complex located on the planet of Coruscant.
Herdessa was a land-based astronomical object that could be found where the Mid Rim Territories and the Slice regions met. Its position was pinpointed as grid square Q-16 on the Standard Galactic Grid. It was situated along the Corellian Run super-hyperroute, in between the astronomical locations of Mon Gazza and Radnor.
In the period spanning 20 BBY to 19 BBY, the Galactic Republic had a blockade surrounding Herdessa during their conflict with the Separatist Alliance known as the Clone Wars. Jedi Generals Anakin Skywalker and Obi-Wan Kenobi were initially assigned to bolster this blockade, but Admiral Wullf Yularen recalled them for a more pressing mission. Nearing the conclusion of the Clone Wars, in the final month before its end in 19 BBY, approximately two thousand legislators, collectively known as the Delegation of 2,000, jointly signed the Petition of 2,000. This petition formally requested that the Republic's Supreme Chancellor Sheev Palpatine give up his emergency powers and work towards peace with the Separatists. Senator Shea Sadashassa, representing Herdessa in the Galactic Senate, was among the signatories of this petition, which was presented during a formal Senate assembly.
However, with the Separatists' defeat marking the end of the Clone Wars, Palpatine reorganized the Republic into the Galactic Empire. Simultaneously, he destroyed the Jedi Order, declaring them enemies. The day following the Empire's establishment, Sadashassa, along with sixty-two other senators who had endorsed the Petition of 2,000, were arrested on accusations of conspiring with a supposed Jedi insurgency. Senators who declared loyalty to the Empire were subsequently released, and Sadashassa continued to serve as Herdessa's senator within the Imperial Senate.
During the Imperial Era, Vryant, a soldier in the Imperial Army, was stationed on Herdessa for six years before being transferred to the planet Phorsa Gedd in the Mid Rim. In 0 BBY, Palpatine dissolved the Imperial Senate, leading to the mass arrest of all senators and former senators. While some managed to escape and go into hiding, Sadashassa and the remaining senators were apprehended by Imperial Security Bureau loyalty officers and imprisoned as political prisoners at the Arrth-Eno Prison Complex on Coruscant, the capital world. An attempt to liberate the prisoners before their scheduled execution around 0 ABY ended with the prison's destruction and the deaths of all the senators inside.
The first mention of Herdessa occurred in Fantasy Flight Games' 2016 roleplaying boxed set, Star Wars: The Force Awakens Beginner Game. Within the Star Wars Legends continuity, Herdessa initially featured in the eighty-eighth issue of Marvel Comics' 1977 Star Wars comic-book series. Mary Jo Duffy wrote the issue, Bob McLeod provided the pencils, and it was released on June 26, 1984.