Editing Sumer (section)

===Uruk period===
{{Main|Uruk period}}
The archaeological transition from the Ubaid period to the Uruk period is marked by a gradual shift from painted pottery domestically produced on a slow [[Potter's wheel|wheel]] to a great variety of unpainted pottery mass-produced by specialists on fast wheels. The Uruk period is a continuation and an outgrowth of Ubaid with pottery being the main visible change.<ref>{{cite book |last1=Henrickson |first1=Elizabeth F. |url=https://books.google.com/books?id=gnpyREWsfG0C&pg=PA353 |title=Upon this Foundation: The N̜baid Reconsidered : Proceedings from the U̜baid Symposium, Elsinore, May 30th–June1st, 1988 |last2=Thuesen |first2=Ingolf |last3=Thuesen |first3=I. |publisher=Museum Tusculanum Press |year=1989 |isbn=978-87-7289-070-8 |page=353}}</ref><ref>{{cite book |author=Glassner |first=Jean-Jacques |url=https://books.google.com/books?id=fhMTRcUm9WsC&pg=PA31 |title=The Invention of Cuneiform: Writing in Sumer |publisher=JHU Press |year=2003 |isbn=978-0-8018-7389-8 |page=31}}</ref>
{{multiple image
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| total_width = 250
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| header = Uruk King-priest feeding the sacred herd
| image1 = Yale University. Uruk period priest-king.jpg
| caption1 = The king-priest and his acolyte feeding the sacred herd. Uruk period, c. 3200 BC
| image2 = Uruk King priest feeding the sacred herd.jpg
| caption2 = [[Cylinder seal]] of the Uruk period and its impression, c. 3100 BC – [[Louvre Museum]]
}}
By the time of the Uruk period, c. 4100–2900 BC calibrated, the volume of trade goods transported along the canals and rivers of southern Mesopotamia facilitated the rise of many large, [[social stratification|stratified]], temple-centered cities, with populations of over 10,000 people, where centralized administrations employed specialized workers. It is fairly certain that it was during the Uruk period that Sumerian cities began to make use of [[Slavery in antiquity|slave labour]] captured from the hill country, and there is ample evidence for captured slaves as workers in the earliest texts. Artifacts, and even colonies of this Uruk civilization have been found over a wide area—from the [[Taurus Mountains]] in [[Turkey]], to the [[Mediterranean Sea]] in the west, and as far east as western [[Iran]].<ref name="Algaze, Guillermo 2005">[[Guillermo Algaze|Algaze, Guillermo]] (2005). ''[[iarchive:urukworldsystemd0000alga|The Uruk World System: The Dynamics of Expansion of Early Mesopotamian Civilization]]'', Second Edition, University of Chicago Press.</ref>{{Rp|2–3}}

The Uruk period civilization, exported by Sumerian traders and colonists, like that found at [[Tell Brak]], had an effect on all surrounding peoples, who gradually evolved their own comparable, competing economies and cultures. The cities of Sumer could not maintain remote, long-distance colonies by military force.<ref name="Algaze, Guillermo 2005"/>{{Page needed|date=August 2021}}

Sumerian cities during the Uruk period were probably [[theocratic]] and were most likely headed by a priest-king (''ensi''), assisted by a council of elders, including both men and women.<ref name="Jacobsen">Jacobsen, Thorkild (Ed) (1939),"The Sumerian King List" (Oriental Institute of the University of Chicago; Assyriological Studies, No. 11., 1939).</ref> It is quite possible that the later Sumerian [[Pantheon (gods)|pantheon]] was modeled upon this political structure. There was little evidence of organized warfare or professional soldiers during the Uruk period, and towns were generally unwalled. During this period Uruk became the most urbanized city in the world, surpassing for the first time 50,000 inhabitants.

The ancient [[Sumerian King List|Sumerian king list]] includes the early dynasties of several prominent cities from this period. The first set of names on the list is of kings said to have reigned before a major flood occurred. These early names may be fictional, and include some legendary and mythological figures, such as [[Alulim]] and [[Dumuzid, the Shepherd|Dumizid]].<ref name=Jacobsen/>

The end of the Uruk period coincided with the [[Piora oscillation]], a dry period from c. 3200–2900 BC that marked the end of a long wetter, warmer climate period from about 9,000 to 5,000 years ago, called the [[Holocene climatic optimum]].<ref>Lamb, Hubert H. (1995). ''Climate, History, and the Modern World''. London: Routledge. {{ISBN|0-415-12735-1}}.</ref>