The chronology of the ancient Near East is a framework of dates for various events, rulers and dynasties. Historical inscriptions and texts customarily record events in terms of a succession of officials or rulers: "in the year X of king Y". Comparing many records pieces together a relative chronology relating dates in cities over a wide area.
For the 3rd and 2nd millennia BC, this correlation is less certain but the following periods can be distinguished:
[1]
Early Bronze Age: Following the rise of cuneiform writing in the preceding Uruk period and Jemdet Nasr periods came a series of rulers and dynasties whose existence is based mostly on scant contemporary sources (e.g. En-me-barage-si), combined with archaeological cultures, some of which are considered problematic (e.g. Early Dynastic II). The lack of dendrochronology, astronomical correlations, and sparsity of modern, well-stratified sequences of radiocarbon dates from Southern Mesopotamia makes it difficult to assign absolute dates to this floating chronology.[2][3]
Middle Bronze Age: Beginning with the Akkadian Empire around 2300 BC, the chronological evidence becomes internally more consistent. A good picture can be drawn of who succeeded whom, and synchronisms between Mesopotamia, the Levant and the more robust chronology of Ancient Egypt can be established. Unlike the previous period there are a variety of data points serving to help turn this floating chronology into a fixed one. These include astronomical events, dendrochronology, radiocarbon dating, and even a volcanic eruption. Despite this no agreement has been reached. The most commonly seen solution is to place the reign of Hammurabi from 1792 to 1750 BC, the "middle chronology", but there is far from a consensus.[4][5]
Late Bronze Age: The fall of the First Babylonian Empire was followed by a period of chaos where "Late Old Babylonian royal inscriptions are few and the year names become less evocative of political events, early Kassite evidence is even scarcer, and until recently Sealand I sources were near to non-existent".[6] Afterward came a period of stability with the Assyrian Middle Kingdom, Hittite New Kingdom, and the Third Babylon Dynasty (Kassite).
Early Iron Age: Around 900 BC, written records once again become more numerous with the rise of the Neo-Assyrian Empire, establishing relatively secure absolute dates. Classical sources such as the Canon of Ptolemy, the works of Berossus, and the Hebrew Bible provide chronological support and synchronisms. An inscription from the tenth year of Assyrian king Ashur-Dan III refers to an eclipse of the sun, and astronomical calculations among the range of plausible years date the eclipse to 15 June 763 BC. This can be corroborated by other mentions of astronomical events, and a secure absolute chronology established, tying the relative chronologies to the now-dominant Gregorian calendar.