The time period might not have to reflect significant events in history it could just be there to help break the game down abit, I just think it makes for a generally more interesting game, as some factions wouldnt be as mind-numbingly difficult in later periods of the game as they are at the start if their were time periods.

It could just follow the expansion of the Roman sphere of influence, I dont know much about pre Augustan Rome but surely there were points when things changed which are worthy of having their own time period? It would also allow for the introduction of other factions that may have emerged after the games starting point.

The lack of civil wars is just ridiculous it makes absolutely no sense, instead of civil wars the game developers seem to have decided that hundreds of annoying rebel brigands would make a decent substitute when really all they do is provide constant annoyance. Its just yet more weight for the argument that RTW is a massive disappointment.