On October 12, 539 BC, the army of Cyrus the Great of Persia takes Babylon. From the article:
"Cyrus takes Babylon
In October 539 BCE, the Persian king Cyrus took Babylon, the ancient capital of an empire covering modern Iraq, Syria, Lebanon, and Israel. In a broader sense, Babylon was the ancient world's capital of scholarship and science. The subject provinces soon recognized Cyrus as their legitimate ruler. Since he was already lord of peripheral regions in modern Turkey and Iran (and Afghanistan?), it is not exaggerated to say that the conquest of Babylonia meant the birth of a true world empire. The Achaemenid Empire was to last for more than two centuries, until it was divided by the successors of the Macedonian king Alexander the Great. A remarkable aspect of the capture of Babylon is the fact that Cyrus allowed the Jews (who were exiled in Babylonia) to return home.
The Histories by the Greek researcher Herodotus of Halicarnassus (fifth century BCE) are the world's first historical study. The account of the Fall of Babylon - which is here presented in the translation by George Rawlinson - proves beyond all reasonable doubt that the author never talked to a Babylonian about the event and never visited the city. He has only two details right: that Cyrus entered Babylonia at Opis, where a battle was fought, and that he captured the ancient city."