It’s Cyrus the Great Day in Iran, the day Cyrus entered Babylon and let the Jews go back to Jerusalem. The city traditionally fell on the 12th of October.
As Daniel told Belshazzar (of writing on the wall fame): “Peres: Your kingdom is divided and given to the Medes and the Persians.” Then, that very night, Belshazzar is slain, though the Book of Daniel attributes the taking of Babylon not to Cyrus, but “Darius the Mede.” Xenophon and Herodotus tell us Cyrus took the city after diverting the Euphrates River.
As Revelations tells us (using Babylon as a code word for Rome):”Babylon the great is fallen, is fallen; and is become the habitation of devils, and the hold of every unclean spirit, and the hold of every unclean and hateful bird!”
I always admired Cyrus, whose right hand, as Isaiah wrote, God had taken; I went and saw the Cyrus Cylinder when it was in DC a year of so ago, and have admired his religious tolerance and administrative skills in empire-building, though empires are frowned upon these days.