A Short History of The Inner Sphere in 3060 of the Common Era (AD)
There is a simple fact which explains much about the current state of the Inner Sphere. There are now five Great Houses (families) in the Inner Sphere -- Davion, Steiner, Liao, Kurita and Marik. Each rules a large portion of known space and competes with the others for total domination. Once, however, there was a sixth great house, House Cameron. The fate of House Cameron is inextricably tied up with the fate of humanity, for better or worse.
House Cameron united the other warring Houses in the Star League in 2571 to bring about a 200 year era of peace, prosperity and technical development unlike any that humanity had known before. In the year 2766 Stefan Amaris, a noble from The Periphery who had come to the court of the First Lord and gained incredible power through his friendship with the young Richard Cameron, killed his young friend, the heir of House Cameron and all of the rest of the members of the Cameron family, and took control of the government. Amaris was eventually put down by General Kerensky and the Star League Defense Force, but by then the Star League itself was unsalavagable. The other Noble Houses having tasted a great deal of autonomy during the long campaign against Amaris, were unwilling to give it up. Each thought he, or she, should be the next First Lord. Kerensky became disgusted with the situation and left the Inner Sphere with 80% of the Star League Defense force. This was the Great Exodus.
With absolutely no central authority left, the Nobles of the Five Houses were completely unrestrained in their lust for the First Lordship and three hundred years of almost continuous warfare brought humanity to its knees economically, militarily, and technologically. Many key technologies, including the ability to build jump capable starships, were very nearly lost. Technology from the Star League era which could not be recreated was called "lostech" and working lostech items became incredibly valuable.
In truth, humanity had entered another Dark Age, very similar to the Middle Ages over a thousand years before. Comstar, the Star League's Ministry of Communications, became the Catholic Church with technology as the all-powerful, monolithic God, and the sainted Jermome Blake as his only prophet.
The situation began to change somewhat in the first half of the 31st Century. A mercenary unit, the Gray Death Legion, found an intact memory core from a Star League Era research library, which when exploited by the scientists at the New Avalon Institute of Science (NAIS), and elsewhere, began to open up certain key technologies to new advances. In particular, the state of medical sciences improved. Further, the marriage of Melissa Steiner and Hanse Davion, and the subsequent unification of the Federated Commonwealth, created the real possibility of reunification. This possibility alone was "enlightening" for many and frightening to others.
Then, in 3049 everything changed. In that year the descendents of the SLDF (Star League Defence Force) returned to the Inner Sphere after nearly 300 years of exile. They came back to save the Inner Sphere from itself. These invaders were the Clans and their initial waves of invasion almost completely devoured the Free Rasalhague Republic (except for six worlds now protected by ComStar forces), took huge pieces out of both the Draconis Combine (including, nearly the DC capital world of Luthien) . Interestingly, the Clan invasion itself has reduced, somewhat, the very in-fighting in the Inner Sphere that their invasion sought to bury. The Federated Commonwealth now stands allied with the Draconis Combine. The Free Worlds League supplies weapons and upgrades to Draconis Combine, Federated Commonwealth and Lyran Alliance forces. And, probably, most dramatically, ComStar has shaken off it's centuries old veil of secrecy and stands alongside the rest of the Inner Sphere in defiance to the Clans.
In fact, it was on the Rasalhague world of Tukayyid in 3052 that ComStar met forces from all six invading clans in a proxy battle for Terra and defeated them all except for Clan Wolf, which met their objectives, and Clan Jade Falcon which was fought to a standstill. The agreement between ComStar and the Clans called for a fifteen year truce which ComStar hoped would give the Inner Sphere time to rebuild and retool their forces.
Ironically, the Clans themselves were not completely unified in their effort and early on cracks began to show in their forces. Politically, the Clans are divided into two camps -- the Crusaders, who believed that it was their destiny to conquer the Inner Sphere and bring peace to the insanity of Inner Sphere politics through force, and the Wardens who believed that it was Kerensky's mandate that the Clans "protect" the Inner Sphere.
The desire to recreate the Star league still dominates the politics of the Inner Sphere (and, in reality, it dominates the politics of Clan space as well). It is the central driving madness of humanity to return to this perceived Golden Age and, literally, all politics in the Inner Sphere has it at its root. Effectively, the periods of interminable warfare leading up to the creation of the Star league and following its destruction have created an inferiority complex in humanity in which this now semi-mythical organization is its only savior. To this end, in 3058 the Five Great Houses of the Inner Sphere, along with most of the minor powers, recreated the Star League at the Whitting Conference on Tharkad (capital of the Lyran Alliance). Sun Tzu Liao was named First Lord and the following year the new alliance launched a massive counter offensive against the Clans, specifically, the Smoke Jaguars.