Sumer4

Sargon periods, and that too much emphasis has been placed on the perception of a "Semitic vs. Sumerian" conflict. However, it is certain that Akkadian was also briefly imposed on neighboring parts of Elam that were previously conquered by Sargon.
Gutian period
ca. 2083–2050 BC (short chronology)
2nd Dynasty of Lagash


Gudea of Lagash
ca. 2093–2046 BC (short chronology)
Following the downfall of the Akkadian Empire at the hands of Gutians, another native Sumerian ruler, Gudea of Lagash, rose to local prominence and continued the practices of the Sargonid kings claims to divinity. Like the previous Lagash dynasty, Gudea and his descendents also promoted artistic development and left a large number of archaeological artifacts. After the fall of their empire, the Akkadians themselves essentially coalesced into two states; Babylon in the south and Assyria in the north of Mesopotamia.
Sumerian Renaissance


Great Ziggurat of Ur, near Nasiriyah, Iraq
ca. 2047–1940 BC (short chronology)
Later, the 3rd dynasty of Ur under Ur-Nammu and Shulgi, whose power extended as far as northern Mesopotamia, was the last great "Sumerian renaissance", but already the region was becoming more Semitic than Sumerian, with the rise in power of the Akkadian speaking Semites and the influx of waves of Semitic Martu (Amorites) who were later to found the Babylonian Empire. The Sumerian language, however, remained a sacerdotal language taught in schools in Babylon and Assyria, in the same way that Latin was used in the Medieval period, for as long as cuneiform was utilised.
Decline
This period is generally taken to coincide with a major shift in population from southern Mesopotamia toward the north. Ecologically, the agricultural productivity of the Sumerian lands was being compromised as a result of rising salinity. Soil salinity in this region had been long recognized as a major problem. Poorly drained irrigated soils, in an arid climate with high levels of evaporation, led to the buildup of dissolved salts in the soil, eventually reducing agricultural yields severely. During the Akkadian and Ur III phases, there was a shift from the cultivation of wheat to the more salt-tolerant barley, but this was insufficient, and during the period from 2100 BC to 1700 BC, it is estimated that the population in this area declined by nearly three fifths.[22] This greatly weakened the balance of power within the region, weakening the areas where Sumerian was spoken, and comparatively strengthening those where Akkadian was the major language. Henceforth Sumerian would remain only a literary and liturgical language, similar to the position occupied by Latin in medieval Europe.
Following an Elamite invasion and sack of Ur during the rule of Ibbi-Sin (ca. 1940 BC), Sumer came under Amorite rule (taken to introduce the Middle Bronze Age). The independent Amorite states of the 20th to 18th centuries are summarized as the "Dynasty of Isin" in the Sumerian king list, ending with the rise of Babylonia under Hammurabi ca. 1700 BC.
During the third millennium BC, there developed a very intimate cultural symbiosis between the Sumerians and the Akkadians, which included widespread bilingualism.[8] The influence of Sumerian on Akkadian (and vice versa) is evident in all areas, from lexical borrowing on a massive scale, to syntactic, morphological, and phonological convergence. This has prompted scholars to refer to Sumerian and Akkadian in the third millennium as a sprachbund.
Akkadian gradually replaced Sumerian as a spoken language somewhere around the turn of the 3rd and the 2nd millennium BC (the exact dating being a matter of debate), but Sumerian continued to be used as a sacred, ceremonial, literary and scientific language in Mesopotamia (Babylonia and Assyria) until the 1st century AD.