Rivers of Civilization will explore the role of environmental factors, and their fluctuations, in the founding stages for civilizations worldwide. We set this in a global context: of evolving climates in times past, and of river and floodplain variability over space and time. These provided both opportunities and threats to riparian communities that can now be much better understood. We stress the very varied global circumstances in which these communities found themselves, even though they were all based on river environments. We also draw lessons for the present day in which riverine environmental challenges are again emerging.