People created cities which required certain parts in order to succeed and civilizations grew:

1)  Govermnents provide some control .
2)  Social structure ususally provides division of labor, in which different people perform different jobs.
3)  Religion or a close relationship with Gods used to explain the forces of nature
4)  Writing is present in some form.
5)  Advanced technical skills either created or acquired through trade.
 
What happens if one or more of these elements is not present?