In 539 BC, the Persian Empire, under Cyrus the Great, conquered Babylon, marking the end of the Neo-Babylonian Empire. This event saw the Persian forces enter the city with minimal resistance, leading to the capture of the last Babylonian king, Nabonidus. The conquest of Babylon by Cyrus the Great is a significant historical event, as it marked the end of Babylonian independence and the beginning of Persian rule over Mesopotamia.