The Legitimate Transbaal Empire was the formal name for both the rebellion and eventual short takeover of the Transbaal Empire instigated by Prince Eonia Transbaal, who crowned himself as the 14th emperor. Before the events of the first game, Eonia advocated for the deeper study and usage of Lost Technology for the purpose of conquest and expansionism. In fear of his growing popularity and dangerous ideals, Gerald Transbaal banished Eonia and his supporters to the unexplored frontier. By a twist of fate, Eonia discovered the Black Moon, the perfect device to administer his vision for the empire and after a few years, he returned to Transbaal to forcibly take the throne with his new automated fleet.
Eonia then focused on accessing the White Moon but before that, he had to take care of one loose end in the form of Shiva, the last surviving member of the royal family. His pursuit of the Elsior was previously attempted by his incompetent field officer Rezon, his trusted friend and subordinate Sherry, and the mercenary group, the Hell Hounds. However, Eonia met his death when the Elsior and its Emblem Frames simply proved stronger than his fleet and the Black Moon revealed its own purpose to merge with the White Moon. The coup finally came to an end with Eonia's death and the Black Moon's destruction.
6 months later however, Rezon, the only surviving member of the coup, was supported by a woman named Nefuria who helped him recover the Black Moon's intact core to rebuild the Black Fleet. Rezon named his movement the True Legitimate Transbaal Empire but soon perished after Nefuria revealed herself to be Val-Fasq.