(or "Subverting History")
I'm not saying anything particularly new when I say that science fiction is rarely about the actual future. It's really more about the present, translated into an allegorical form, and the venerable "Battletech" franchise is no exception. It doesn't even really disguise it, with the various Great Houses of the Inner Sphere being clear analogies of various Earth nations--it doesn't really make much sense when you sit down and analyze it that these lines of sheer demarcation between a Japanese monoculture, a Chinese monoculture, et cetera would actually translate across hundreds of light years and centuries into the future, but it makes emotional sense to us because it's a recognizable allegory for our world. It feels right that in the fall of the Star League (Rome), the Inner Sphere (Europe) would splinter into bickering, warring nation-states constantly jockeying for political advantage, with ComStar (the Catholic Church) as the primary mediator of disputes. (You could probably write a paper on the symbolism of ComStar, guardians of faster-than-light communications, acting in the role of priests, but not today.)
But having built a universe that makes emotional sense to us, complete with a sympathetic British/American heroic House as the hero (the Federated Suns sort of blend that line as necessary, much like House Marik straddles a line between American and Prussian--again, you could probably do a paper on the way that two of the major strains of American ancestry are divided up in the Battletech universe)...having set up the universe to feel comfortable to us armchair historians, Battletech deliberately subverts the audience's expectations of how this "future history" will flow. So we see the allegorical China joining with Japan and Germany to repel an invasion by Britain and Norway, then a shift as the alliance between the latter two falters and the Japanese analog winds up allied with the pseudo-Britain, while the futuristic church of ComStar splinters along ideological lines--OK, so that bit's fairly historically accurate, but you get my point. Having established factions that we recognize, the Battletech writers then have them behave in ways that are very different from their historical analogs, which serves to heighten the sense of surprise at every plot twist.
The ultimate example of this is, of course, the Clans. The first era of Battletech books established the legend of "the Star League", the united and glorious nation that splintered into the various Great Houses. It felt comfortable, understandable, the kind of legend that you see a lot in fantasy and science fiction. The Star League drew upon historical Rome (which wasn't nearly as benevolent or enlightened as its legends would indicate, but that's what happens when you write all the history books) to create a backstory that made emotional sense to the readers. Nobody saw it coming when the lost legions of the Star League came back as ticked-off, bloody-minded Spartan-style conquerors sweeping waves of devastation through the Inner Sphere and forcing them into a tenuous alliance, any more than you'd expect to hear about the Roman legions coming back in World War II armed with machine guns. It was a complete paradigm shift in the whole concept of the Battletech universe, and yet one that was foreshadowed expertly in hindsight.
Once the Clans opened up the second era of the Battletech universe, it was even easier to generate real suspense. If something so major could change so rapidly, then surely just about anything could happen? And in some ways, it did. Several major plot twists marked the later Battletech novels of this era, as the political maneuvering reached a fever pitch. Unfortunately, many of the storylines were left unfinished as the property changed hands and jumped ahead about sixty years (to the "Dark Ages" era.) Still, that decision is in some ways typical of the Battletech line. It remains strong and vital in some ways because of the writers' willingness to take risks. There are no sacred cows in the Battletech universe, not even history itself.