Ryo Fortress served as the stronghold of Clan Ryo on the world of Shikaakwa, a planet. It functioned as the center of authority for the crime lord who headed the clan. Following the conclusion of the Despot War, Baron Volnos Ryo became the leader of the clan, his father having previously met his death at the hands of Queen Hadiya.
In the year 25,793 BBY, a battle took place at Ryo Fortress, situated on the planet Shikaakwa. This conflict involved the frenzied warrior Daegen Lok and his ally Xesh, facing off against a squad of Je'daii dispatched to apprehend them. Lok, Xesh, and their captive Shae Koda made their way to Ryo Fortress to seek backing from Clan Ryo and its leader Volnos Ryo. However, the arrival of Je'daii Rangers Hawk Ryo and Rori Fenn, along with Je'daii Journeyer Sek'nos Rath and the stranger Trill, triggered a widespread battle. The skirmish concluded when Koda successfully persuaded Xesh to align with the Je'daii, resulting in Lok's capture and subsequent return to Tython.
In the aftermath of the Despot War, numerous inhabitants of Shikaakwa, notably including the Crime Lords, abandoned the fortress. They continued to harbor resentment towards the New Je'daii Order and desired retribution. A mysterious Je'daii, shrouded in darkness, arrived on the planet and eventually reached the deserted fortress. Within its walls, they uncovered ancient inscriptions that would lead to the genesis of the antithesis to the Light side of the Force, eventually known as the Dark side of the Force.