Why did mashkan shapir collapse?

One theory has to do with the shift in river courses of the Tigris-Euphrates system, effectively "Drying up" the region making it largely uninhabitable. This Begins to occur during the reign of Samsu-Iluna in the late 18th century B.C.E. If you are interested in finding more Id get a copy of "The Anatomy of a Mesopotamian City: Survey and Soundings at Mashkan-shapir" Edited by Elizabeth C. Stone and Paul Zimansky.

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