Americans are really fortunate - this ancient object is currently ( I believe) touring through America, courtesy of the British Museum.
It's the Cyrus Cylinder, likely the first statement of Human Rights in history. Impressive? Well, the Jews thought so, they managed to re-write their history somewhat and make room for Cyrus to be the Messiah of Yahweh. So this probably Zoroastrian worshipper became associated with Judaism and then Christianity and his title of Shahenshar - King of Kings borrowed for Jesus.
The Iranchamber has a translation, if you'd like to read it. http://www.iranchamber.com/history/cyrus/cyrus_charter.php
And the Director of the British Museum discusses its significance and the reaction of contemporary Iranians when it was exhibited in Iran:
http://www.economist.com/blogs/prospero/2013/03/neil-macgregor-cyrus-cylinder