Answer: The Greeks won a decisive victory, losing only 192 men to the Persians' 6,400 (according to the historian Herodotus).
To govern the citizens, keep the land civil, and stop it from plundering into anarchy. Its to keep order, and keep its citizens happy, just like in Civilizations. To keep your people happy, increases production, and many other important things, that you need.
Centrism is support of a balance between social hierarchy and social equality. Centrists are not strongly politically left or right wing.