What caused the collapse of the cilvilization in Sumer and Assyria?

Question

History.

Answer 1

Sumer fell to an Elamite invasion during the rule of Ibbi-Sin (ca. 2004 BC). It is believed that invasion was successful because Sumerian agriculture was in decline, so Sumer could not maintain a sufficient army. The root causes of that decline are still debated; some say it was caused by a long period of drought, others, that it was an inevitable consequence of Sumerian irrigation, which caused increasing salinization of the soil and decline in its fertility.

Assyria was conquered by the neo-Babylonian Chaldean dynasty; its capital, Nineveh, was sacked in 612 BC.

Answer 2

Decline Of Sumer