These are commercial, but you may like them too:
Koei's Romance of the Three Kingdoms is a very good franchise about civilization, war and Chinese history. It has old as well as recent titles.
Uncharted Waters, also from Koei, is also very nice, albeit a bit far from the "mass human behavior" scenario, but the historical background (although at times a bit inaccurate) can be very enchanting. I also heard there is a recent MMO version of that.
Chimerica: another old game for the list. It is about a fictional in Latin America during cold war. Focus is on the political side of things, but still a VERY interesting game. IMO, it could resemble a text-based political game, but check for yourself.
Fallout Series: A game which has for scenario post-nuclear-armageddon Earth. Seems to ponder on how would it be like if WW2 had ended in nuclear armageddon.
Those and Civilization (mainly IV and V) are very good and content-rich games. Final Fantasy VII could also be counted as an allegory to environmental disaster.
Such games can be found for a low price now, as they have been released for some time now. Those very old can be found for cheap at
www.GOG.com <- a site that sells very old games.
Although those games can be nice interesting, they sometimes tend to be inaccurate and/or biased. To really learn something I would enroll to a Social Sciences course at an university or Fachhochschule - if they really do have something similar. It is true that in those places there may be also be biases, but can also be considered, if you have enough free time. Also, they may count professionaly.