In Imperator: Rome, each nation must keep increasing its Civilization Value to be able to develop new technologies.
Civilization Value shows the advancement level of your nation, represents its infrastructure level, urbanization, and other novelties used by your citizens. Each town has its own Civilization Value. All cities within your state will slowly raise their Civilization Value to the national Civilization Value, which is increased by forms of governments and technologies. Your towns will always be striving for this limit, even if you somehow got hold of an excess of these points. Remember - barbaric attacks will lower your Civilization Value by a dozen points. Remember to always protect your borders from barbaric hordes.
Civilization Value affects two important aspects. First, it reduces the level of population growth of barbarians in nearby regions. If you want to get rid of a barbarian enclave, you have to make your cities to quickly put civilization pressure on their settlements. Thanks to that, you will get rid of barbarians.
Secondly, Civilization Value affects the happiness and development of your citizens. The higher the Civilization Value, the faster the population growth in this region. High Civilization Value has a positive effect on your citizens and freemen's happiness. However, it has a negative effect on tribesmen. Be sure that Civilization Value is high in densely populated cities. If you have numerous tribesmen, think about promoting them to freemen to avoid penalties. Civilization Value has another positive effect - it increases supplies for your army. Thanks to that you can feed more cohorts in that city and increase the safety of your citizens.