The Council generates Science every time the city grows, and is available very early. Build this building if you wish to have a technological advantage over your rivals, though the value of this advantage diminishes as the city becomes larger.
A Council is a governing body in an organised community. It is most common in subsistence cultures, with council membership being the condition or quality of being a political leader of a community. Over time, as communities grew, the importance of councils diminished in favor of larger governing institutions.