Babylon was the capital city of Babylonia, a kingdom in ancient Mesopotamia, between the 18th and 6th centuries BC. It was built along the left and right banks of the Euphrates river with steep embankments to contain the river's seasonal floods. Babylon was originally a small Akkadian town dating from the period of the Akkadian Empire c. 2300 BC.
The town became part of a small independent city-state with the rise of the First Babylonian dynasty in the 19th century BC. The Amorite king Hammurabi created a short-lived empire in the 18th century BC. He built Babylon into a major city and declared himself its king. Southern Mesopotamia became known as Babylonia and Babylon eclipsed Nippur as its holy city. The empire waned under Hammurabi's son Samsu-iluna and Babylon spent long periods under Assyrian, Kassite and Elamite domination. After being destroyed and then rebuilt by the Assyrians, Babylon became the capital of the short-lived Neo-Babylonian Empire from 609 to 539 BC. The Hanging Gardens of Babylon were one of the Seven Wonders of the Ancient World. After the fall of the Neo-Babylonian Empire, the city came under the rule of the Achaemenid, Seleucid, Parthian, Roman, and Sassanid empires.
It has been estimated that Babylon was the largest city in the world c. 1770 – c. 1670 BC, and again c. 612 – c. 320 BC. It was perhaps the first city to reach a population above 200,000. Estimates for the maximum extent of its area range from 890 to 900 hectares (2,200 acres).

The remains of the city are in present-day Hillah, Babil Governorate, Iraq, about 85 kilometres (53 mi) south of Baghdad, comprising a large tell of broken mud-brick buildings and debris.

The University of Babylon (Arabic: جامعة بابل) is a university located in Babylon, Iraq. It consists of 20 colleges within three compounds, located seven kilometers south of the city of Hillah, in Babylon Province. The campus was originally the Administrative Institute of Babylon. Later some of the buildings were adopted for use by the medical college of the University of Kufa, before being established as a university in its own right in 1991.
The university now teaches a wide variety of subjects, and during the 1990s, started teaching night classes. These became popular, especially among well-off families, after the increase in difficulty of high school examinations in 1997.
It publishes the Journal of University of Babylon and Medical Journal of Babylon.