History of Mesopotamia - Short Outline of Mesopotamia - Chronology and Periodization

Chronology and Periodization

Further information: Chronology of the ancient Near East, ASPRO chronology and Dating methodologies in archaeology

Two types of chronologies can be distinguished: a relative chronology and an absolute chronology. The former establishes the order of phases, periods, cultures and reigns, whereas the latter establishes their absolute age expressed in years. In archaeology, relative chronologies are established by carefully excavating archaeological sites and reconstructing their stratigraphy – the order in which layers were deposited. In general, newer remains are deposited on top of older material. Absolute chronologies are established by dating remains, or the layers in which they are found, through absolute dating methods. These methods include radiocarbon dating and the written record that can provide year names or calendar dates. By combining absolute and relative dating methods, a chronological framework has been built for Mesopotamia that still incorporates many uncertainties but that also continues to be refined. In this framework, many prehistorical and early historical periods have been defined on the basis of material culture that is thought to be representative for each period. These periods are often named after the site at which the material was recognized for the first time, as is for example the case for the Halaf, Ubaid and Jemdet Nasr periods. When historical documents become widely available, periods tend to be named after the dominant dynasty or state; examples of this are the Ur III and Old Babylonian periods. While reigns of kings can be securely dated for the 1st millennium BC, there is an increasingly large error margin toward the 2nd and 3rd millennia BC.

Based on different estimates for the length of periods for which very few historical documents are available, so-called Long, Middle, Short and Ultra-short Chronologies have been proposed by various scholars, varying by as much as 150 years in their dating of specific periods. Despite problems with the Middle Chronology, this chronological framework continues to be used by many recent handbooks on the archaeology and history of the ancient Near East. A study from 2001 published high-resolution radiocarbon dates from Turkey supporting dates for the 2nd millennium BC that are very close to those proposed by the Middle Chronology.