Which Came First? Canals Or Cities

Irrigation canals arose so long before cities did that these canals and the agriculture that they are a testament to, couldn't have been the reason that cities came to be. So, maybe religion and not agriculture is the key factor.

The latest data from Ancient Mesopotamian city of Girsu shows that agriculture built around system of irrigation canals existed for a 1000 years before the first city was built.

From the Old European Culture blog. 

The excerpt below is from the body text of the linked article (an educated layman's level publication, not a scientific journal):

Rey and his team used new technologies to understand the development of the city, flying drones over the vast, 250-hectare site. The images they gathered show the extent to which the irrigation system was embedded throughout the city and its surrounds.

Heavy rainfall, a product of climate change, also washed away the top layer of the soil, making the outlines even more apparent. 

Working with archaeologists from five universities in Iraq, led by Jaafar Jotheri of Al Qadisiyah, the British Museum team dug out shells and other material from the bottom level of the canals to be carbon-dated. The results were startling: the canals seem to have been dug in the fifth millennium BC. .

“The big surprise is that the largest irrigation canals date to the prehistory of Mesopotamia. That means they are much, much older than the birth of the city, by about 1,000 years," says Rey. "Traditionally, what you read is that development in Mesopotamia begins at the end of the fourth millennium, around 3300 BC. That’s when there was an important transition from pre-urban to urban and the invention of writing.

"But the canals that we have dated recently sets the date back to the fifth millennium, which means that irrigation is not the key, the spark that triggered the urban construction and the invention of writing. And that's a really important discovery.”

Before, archeologists believed that once the ancient Sumerians learnt to irrigate their crops, they were able to move from subsistence farming to the social and religious hierarchy that the elaborate temples of Girsu attest to.

But the Girsu Project’s discoveries, which Rey has written up for a paper that has passed peer review but which is still to be published, show that the Sumerians were living with well-watered plains for a full millennium before they began to build the temple complexes.

What changed? What moved the needle towards a more complex society?

Rey speculates that the shift was unrelated to the environment but rather owed to the pattern of thinking of those living in Girsu: an ideological transformation. Temples and administrative buildings allowed the powers ascribed to the gods to reside in one site, which was embedded into a larger social and political structure.

“It was a domestication of the power of the gods,” Rey says, in an adaptation of the phrase usually used for Sumerian development of the domestication of water.