Following unsuccessful attempts to keep the descendants of Nebuchadnezzar II on the throne, the usurper Nabonidus became king. Persian tribes had moved into Elamite lands, and the Medes made Harran a dangerous city; Nabonidus‘ mother, an aged acolyte of Ashurbanipal, resided there. His lengthy inscriptions are informative about his deeds and his character. He dedicated his daughter to the Moon-god at Ur according to precedent, and spent ten years in Arabia, leaving his son Belshazzar in charge in Babylon. He returned and restored the temple in Harran. Cyrus the Great brought his rule to an end, but continued to employ some high officials. Cyrus was probably of mixed Elamite and Persian descent. The Cyrus Cylinder, inscribed in Babylonian cuneiform for a Babylonian audience, used traditional denigration of the previous king Nabonidus, and acknowledged Marduk as Babylon’s god. In another cuneiform text, Nabonidus was mocked for his scholarly pretensions and for sacrilegious acts. Babylon continued to be the centre where all subsequent kings felt obliged to celebrate the New Year festival to be accepted as legitimate rulers. Old monuments were not defaced. Cyrus may have been responsible for an imitation of Babylon’s glazed bricks at Persepolis. He made his son Cambyses co-regent.

The First Dynasty, an unbroken succession of Amorite kings, lasted 300 years despite a major rebellion. Babylon had close relationships with the nearby cities Sippar, Kish, and Borsippa. Trade and alliances reached much further. The Sumerian king-lists of earlier times were replaced by Babylonian equivalents, various cities having their own version. Kings briefly recorded major events; names were given to each year of their reign for dating documents. Trade was widespread, by canal and river, or overland by donkey. Royal edicts excluded certain groups from trade. Evidence comes from a profusion of clay tablets. Official letters are plentiful. Priestesses of Marduk carried out trade for Babylon in other cities. The temple of Marduk was built and furnished with a golden throne. Elamite control over several major cities, which left its mark on temple design, was ended by Hammurabi late in his reign; there is a possible connection with Genesis 14:1–16. Regular edicts were issued to release individuals from debt and to regulate trade. The main powers were Halab (Aleppo), Eshnunna, and Larsa, until Hammurabi achieved supremacy and claimed divinity. His successor Samsu-iluna followed his father’s example.