The Triangulum galaxy is the 3rd largest galaxy in the Local Group, being far smaller than the Andromeda and the Milky Way galaxies. It has a diameter of 60,000 light years, making it about as third as large as the second largest galaxy, the Milky Way (estimated to have a diameter up to 200,000 light years). Within the galaxy are an estimated 40,000,000,000 stars, less than one twelfth of those in the Milky Way galaxy (estimated to have up to 500,000,000,000 billion stars).
The Than Hegemony is the oldest interstellar power in the galaxy, the second interstellar power in the Local Group to have achieved slipstream capability. After the fall of the System Commonwealth, the Than Hegemony reestablished itself as an interstellar power becoming the 2nd most powerful one in the Local Group, after the Drago-Kazov Pride.
In 7756 CY, the Than-Thre-Kull, who were the only other species to have developed slipstream capability independently from the Commonwealth, petitioned the Systems Commonwealth for membership and were accepted in 7762 CY. Centuries later in 9112 CY, the environmentally devastated Nightsider homeworld was made a protectorate of the Commonwealth. They ended up being evacuated and dispersed across known space. Centuries of peace followed, which ended with the first Magog attack on the Commonwealth in 9766 CY. The conflict with the Magog lasted till 9781 CY upon the signing of the Treaty of Antares.
Which led to the Nietzschean Rebellion, which began in 9784 CY. During the first year of the war, Than-led Home Guard units repulsed a Nietzschean attempt to conquer San-Ska-Re the Than homeworld. By 9785 CY, the Nietzscheans had conquered most of the inhabited worlds in the Andromeda and Milky Way galaxies, therefore San-Ska-Re became the Commonwealth's provisional capital. The war ended in 9786 CY, and the Nietzschean Alliance collapsed in the following year. Soon afterwards in the same year, the Magog returned, attacking both Nietzchean and former Commonwealth worlds.
In 9856 CY, a coalition of Than worlds reestablished the Than Hegemony, which established its control over most of the Than dominated worlds. They ended up controlling the most stable territory within known space. One in which other species continued to live on Than-majority worlds, most of whom adapted well to Than society. Circa 10088-10090 CY, the capital of the New Systems Commonwealth was established on Tarazed, an isolated Commonwealth outpost that was founded by Dr. Sara Riley during the Nietschean Rebellion. In 10091 CY, it was the site of the final battle of the Second Systems Commonwealth Civil War, that had started the previous year. The Commonwealth fleet engaged the attacking Nietzschean fleet in high orbit, and emerged victorious over the Nietzscheans.
- Enkindu: Planet controlled by the Sabra-Jaguar Pride.
- Inaris: The homeworld of the Inari.
- Krrendar IV: The Nightsider homeworld, Former Nightsider planet pyroformed by the Pyrians.
- San-Ska-Re: Than-Thre-Kull homeworld.
- Schopenhauer's World: Planet controlled by the Sabra-Jaguar Pride.
- Tarazed: A planet colonized by a number of Humans and loyalist Nietzscheans, surviving crew of the Andromeda Ascendant, and the Starry Wisdom, lead by Sara Riley.
- Zhu-Zhu Hwai: The Umbrite homeworld.