The town became part of a small independent city-state with the rise of the First Babylonian dynasty in the 19th century BC. After the Amorite king Hammurabi created a short-lived empire in the 18th century BC, he built Babylon up into a major city and declared himself its king, and 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 was one of the Seven Wonders of the Ancient World, although a number of scholars believe these were actually in the Assyrian capital of Nineveh. After the fall of the Neo-Babylonian Empire, the city came under the rule of the Achaemenid, Seleucid, Parthian, Roman, and Sassanid empires.