quality:corruption, structural:summarization, quality:correction, stylistic:style_transfer, information:classification
Old Babylonian period

According to a Babylonian king list, Amorite rule in Babylon began (c. 19th or 18th century BC) with a chieftain named Sumu-abum, who declared independence from the neighboring city-state of Kazallu. Sumu-la-El, whose dates may be concurrent with those of Sumu-abum, is usually given as the progenitor of the First Babylonian dynasty. Both are credited with building the walls of Babylon. In any case, the records describe Sumu-la-El's military successes establishing a regional sphere of influence for Babylon.

Babylon was initially a minor city-state, and controlled little surrounding territory. Its first four Amorite rulers did not assume the title of king. The older and more powerful states of Elam, Isin, and Larsa overshadowed Babylon until it became the capital of Hammurabi 's short-lived empire about a century later. Hammurabi (r. 1792–1750 BC) is famous for codifying the laws of Babylonia into the Code of Hammurabi. He conquered all of the cities and city states of southern Mesopotamia, including Isin, Larsa, Ur, Uruk, Nippur, Lagash, Eridu, Kish, Adab, Eshnunna, Akshak, Shuruppak, Bad-tibira, Sippar, and Girsu, coalescing them into one kingdom, ruled from Babylon. Hammurabi also invaded and conquered Elam to the east, and the kingdoms of Mari and Ebla to the northwest. After a conflict with the Old Assyrian period king Ishme-Dagan, he forced his successor to pay tribute late in his reign.

After the reign of Hammurabi, the whole of southern Mesopotamia came to be known as Babylonia. From this time, Babylon supplanted Nippur and Eridu as the major religious centers of southern Mesopotamia. Hammurabi's empire destabilized after his death. The far south of Mesopotamia broke away, forming the native Sealand Dynasty, and the Elamites appropriated territory in eastern Mesopotamia. The Amorite dynasty remained in power in Babylon, which again became a small city state. After the destruction of the city the Kassites rose to control the region.

Texts from Old Babylon often include references to Shamash, the sun-god of Sippar, treated as a supreme deity, and Marduk, considered as his son. Marduk was later elevated to a higher status and Shamash lowered, perhaps reflecting Babylon's rising political power.