In Jenkins' works ('New Faces of Christianity, 'Next Christendom') somewhere he tells the story of the Africen villagers moving into the city, and seeking the community that is like that which they left. They find it in the church.
Africa was 10% Christian in 1900, it's over 46% now. Happening at the same time may not be causation, but...
2.Stiglitz (won Nobel Prize) says that the 2 keys to the 21st C. are Chinese urbanization and American innovation.
Here's how China has urbanized. It an amazing visual of the Pearl River Delta. It has local areas as big as Western cities.
3. There are other ways of forming communities, and destroying them (Jane Jacobs) but a wise planner would take these 'facts' (done things, think 'factory) into account, and ordinary folks would Prais the Lord Providence, and carry on with respective callings.