The Eternal Throne was the ceremonial throne of the Emperor of the Eternal Empire, located at the peak of the Spire above the atmosphere of the planet Zakuul.
Designed and built by generations of Zakuul's greatest minds at the behest of their Emperor Valkorion, the Eternal Throne is connected to a hyperwave relay station ten kilometers below the Spire, powered by two hundred generators that tap into Zakuul's core that allowed its occupant to communicate with and control the GEMINI units that ran the Eternal Fleet. The term "Eternal Throne" was also used to refer to the rulership of the Eternal Empire, and later on, in the post-Galactic War era, rulership of the whole galaxy.
Valkorion's children Arcann and Vaylin have both sat on the Eternal Throne after his public death.
Until the end of his reign, Valkorion decided that his children, Arcann and Vaylin, were unworthy of the Eternal Throne, and thus when his essence inhabited the Outlander, made his clear intention for the Outlander to take the throne in his place. Following the overthrow of Arcann, and the subsequent death of Vaylin, the Eternal Fleet went rampant, attacking worlds such as Coruscant, Dromund Kaas, and Zakuul itself. The Outlander returned to Zakuul and sat upon the throne, pacifying the Eternal Fleet. However, Valkorion attempted to take control of the Outlander's body, leading to a war within the Outlander's mind that ended with the final death of the Immortal Emperor. With Valkorion destroyed and the Eternal Empire subsumed into the new Eternal Alliance, the Throne's control mechanisms were relocated to the Alliance base on Odessen.
After the decimation of the Eternal Fleet, the Gravestone and Zildrog, the Eternal Throne was subsequently destroyed as a direct result of those losses leaving the Eternal Alliance at a huge loss.
The Eternal Throne features heavily in the Knights of the Fallen Empire and Knights of the Eternal Throne expansions to Star Wars: The Old Republic. The player seizes control of the Eternal Throne in Chapter IX of the Knights of the Eternal Throne campaign. How they choose to wield it is up to the player.
Concept art of the Eternal Throne Room
If the player elects to lead the Alliance as a peacekeeper (light side choice), the Throne's control mechanisms are installed in an updated war room. However, if the player elects to become the new Emperor/Empress (the dark side choice), the Eternal Throne is set up in an actual throne room, similar to the Spire on Zakuul.
Additionally, if the player made consistent light side choices up to that point, they will be accompanied into the throne room by Senya Tirall and a redeemed Arcann. If the player elected to kill both Senya and Arcann (in Chapter I and Chapter VI, respectively, of Knights of the Eternal Throne), they are accompanied by Theron Shan and Lana Beniko.