Sounds like an MMO Strategy game I used to play...think it was called Shattered Galaxy.
Anyways, from the way I took the description, the bad thing about history is that you knew who won that particular war. So who's to say that when that particular war is triggered that a player switched sides (most likely hardcore fans) due to the fact that based on historical reference, that faction won. (Bandwagoning)
If I am wrong about that and if the other faction that wasn't supposed to win (based on historical references) DID win. That pretty much changes history and changes the storyline altogether! (/Insert 'Back to the Future' Reference here)
Other than this, I'm pretty sure it's just scripted battles. Both sides fight each other during that war timeline and developers will pretty much stop the fight and tell a story in a bulletin somewhere that the fight is over and a settlement came to pass -- No matter how much the opposite team dominated.
Anyways, from the way I took the description, the bad thing about history is that you knew who won that particular war. So who's to say that when that particular war is triggered that a player switched sides (most likely hardcore fans) due to the fact that based on historical reference, that faction won. (Bandwagoning)
If I am wrong about that and if the other faction that wasn't supposed to win (based on historical references) DID win. That pretty much changes history and changes the storyline altogether! (/Insert 'Back to the Future' Reference here)
Other than this, I'm pretty sure it's just scripted battles. Both sides fight each other during that war timeline and developers will pretty much stop the fight and tell a story in a bulletin somewhere that the fight is over and a settlement came to pass -- No matter how much the opposite team dominated.