Colonization of the Inner Sphere began in 2108 when the Terran Alliance launched the first manned faster-than-light mission aboard the TAS Pathfinder. Between 2108 and 2235, the Terran Alliance colonized and ruled the first centralized interstellar government in human history, controlling more than 600 colonies within 120 light years of Terra. However, corruption and logistics made it impossible to adequately govern such a large body. Private concerns "illegally" funded exploration and colonization of Inner Sphere worlds as well as worlds located in the Periphery and the Deep Periphery. Despite the best efforts of the Terran Alliance to end "blockade running", by the end of the Outer Reaches Rebellion, the Terran Alliance was declining.
The Outer Reaches Rebellion was an interstellar war fought by the Alliance between 2236 and 2237. The rebellion started on the world Freedom, as a protest against taxation and directed at the corrupt Alliance government that controlled the planet. The proverbial straw that broke the camel's back came when Colonial Terran Governor Ardath Rathill imposed one tax scheme too many.
(2237) Captain Robert Davion of the 6th Colonial Marines deserts his post and provides rebels with Marine equipment and military advice, eventually joining as one of the senior Lieutenants
From c. A.D. 2300 to 2787, the Inner Sphere was divided into five "pie wedges" around a central, roughly circular core:
For those of you who participated in the Battle of Tharkad Faction Play event, here are the stats, finally! (Apologies for the wait!)
Total Wins for IS:Siege: 1674