The New Thallonian Protectorate was formed around 2377 by Si Cwan, one of the only surviving members of the Thallonian royal family. Si Cwan became it's first Prime Minister The Protectorate was a democratic body designed to provide stability to the former subjects of the Empire. There were fifty-seven member worlds in the Protectorate. (NF novel: After the Fall)
The Grand Chamber of the New Thallonian Protectorate is designed as a series of concentric circles, with seating arranged like that in a stadium. Naturally, there was much debate about exactly how to decide which representative sat at which level. Ultimately they settled on the simplest, most non-discriminatory method: geography. The worlds whose orbits brought them closest to New Thallon sat at the front, closest to the twin tables of the prime minister and prime arbiter. (NF novel: After the Fall)
In 2379, the extra-dimensional beings known as the Teuthis, through their catspaws, the Priatians, attempted to incite civil war in the Protectorate. The Teuthis hoped to destabilize the area for eventual conquest. (NF novel: After the Fall)
Fhermus paraded Cwan's head before Cwan's widow, Robin Lefler and Starfleet captain, Katerina Mueller. The last thing Fhermus expected was for the grieving widow and the Starfleet captain to attack him. Mueller avenged Cwan's death by stabbing Fhermus through the heart.
Leadership of the New Thallonian Protectorate passed on to Si Cwan's sister, Kallinda, and his widow, Robin.