We thought we were @ peace?
It happened because the consuls only cared about their own personal wealth and not for the people. The senate got richer and richer while the people got poorer and poorer. It ended with the rise of the Empire and the rule of an Emperor. The disadvantage was that all of the power was in the hand of a single person and often the Roman emperors were tyrannical.
I believe it is Partisan. Is this one of your options? :)
Its because science came to be that it relied on big projects. I hope I could help! :D
