After the Renaissance, the city slowly lost its political independence, but by that time it was ruling the world : in the middle age the nobility was living in its castle in the countryside ; in the 18th century it was living in luxurious hostels in the city.

Indeed the first intellectual evolutions appeared in Mesopotamia, at the time of the Sumerians which seems to have been of the city state ; Greeks were organized along city-state lines but the Hellenistic period (i.e. empires left over after the death of Alexander the Great) had the emperor-as-deity, yet saw the summits of Greek thoughts.

Romans are boring, have little litterature and next to no philosophy and science. It's not amazing the Roman intelligentsia spoke in Greek, not in Latin.

As for the mongols, because they had destroyed the Arab middleman between Europe and China, and instituted peace in Central Asia, they made possible the coming of Europeans in Cambaluk ; i.e. Marco Polo. Europeans who brought back the plague when coming back...

Un roi sans divertissement est un homme plein de misères