Thallonian prince Si Cwan (2342-2379) was one of only two members of the Thallonian royal family to survive the fall of the Thallonian Empire in the year 2373. He later managed to unite the worlds of the former Empire in sector 221-G into the democratic New Thallonian Protectorate.
Si Cwan was born into the Thallonian Royal family in the year 2342. By the age of seven, he was participating in ritual hunts. At the age of eight, he witnessed the total destruction of the planet and people of Rolisa, which was consumed by the ravenous Black Mass. Si Cwan was trained in the ways of stealth and self-defence by Jereme, a Kotati who was considered to be one of the greatest living combat masters. Also training with Jereme at that time was a human named Sientor Olivan.
Cwan learned his first valuble lesson about Thallonian politics in 2356, when he discovered that his best friend, Zoran Si Verdin, was actually spying on him on behalf of his father, the Emperor.
In 2363, Cwan allowed a Vulcan Starfleet officer named Soleta to escape from the dungeons of Thallon when she was sentenced to death for trespassing in Thallonian space.
Unlike most of his family, Si Cwan was well-liked and respected by the Thallonian people. Cwans concerns were for the welfare of the people of the Empire, and not of the Empire itself. Cwan swore that when he ruled, he would make the Empire a better place for its people. Unfortunately, he never got the chance-the Thallonian Empire fell in 2373, because of a coup against the royal family that left almost all of them dead. It was engineered in part by a neighboring hostile species, the Danteri, who had also invaded and occupied nearby Xenex, prompting a rebellion against their oppression three centuries later, led by M'k'n'zy of Calhoun, who who later become known as Mackenzie Calhoun after he joined Starfleet.
The center of Cwans existence, the only person he truly loved, honored, and trusted, was his sister, Kalinda.
After the fall of the Thallonian Empire, Cwan appealed to Starfleet to join the USS Excalibur (NCC-26517) on its relief mission to the fallen empire. When his request was rejected by Admiral Edward Jellico, Cwan convinced Soleta, who was assigned to the Excalibur as science officer, to smuggle him aboard. After appealing directly to Captain Mackenzie Calhoun, he was allowed to stay aboard, in the role of unofficial Thallonian ambassador.
Cwan continued his quest for a unification of the former worlds of the Empire on the USS Excalibur, which launched in mid-2376. He also became aware that his assistant, Robin Lefler, had long had romantic feelings for him, and that he shared those feelings. When Si Cwan's efforts to create a New Thallonian Protectorate finally bore fruit circa 2377, Cwan asked Robin to marry him. Robin accepted, leaving the Excalibur and accepting the position of Starfleet liaison to the Protectorate. By 2379, the New Thallonian Protectorate had brought much needed stability to Sector 221-G. Cwan lead the protectorate with Fhermus, a Neklarite who was the father of Kalinda's fiancee', Tiraud.
When Kalinda apparently murdered Tiraud on the night of their wedding, civil war threatened to tear the fragile Protectorate apart. (NF novel: After the Fall)
After sending Robin away for her own safety, Cwan discovered that Kalinda had been abducted and replaced by a shape-shifting member of the extra-dimensional Teuthis, with the intention of fomenting civil war. While Cwan tried to prevent hostilities, Fhermus used the confusion to launch a coup. Cwan was captured by Fhermus' forces, and he was unceremoniously executed in a New Thallon dungeon.
Kalinda immediately sensed her brother's death, and later, using her ability to talk to the dead, informed him of Fhermus' eventual defeat and her and Robin's ascension to power in the Protectorate.
After the kidnap of his son, Si Cwan's ghost possessed Kalinda's body to aid in the search for him. During that time, he slept with Tania Tobias of the Excalibur. Upon the return of Cwansi, he returned to the Spirit World.