Rocketman123:
Many modern biblical researchers were skeptical about the wording of the declaration as described in the Book of Ezra. Among other things, they claimed that it was improbable that a Persian king would have made a declaration in Hebrew or declared that he was acting as a messenger of the God of Israel.
But archeological excavations conducted in the ancient city of Babylon in 1879, discovered a clay cylinder bearing a long inscription in Akkadian. The inscription included a plea made by King Cyrus to the Babylonians in which he declared that he had acted on behalf of the Babylonian god Marduk. "I, Cyrus King of Babylonia… Marduk the Great Lord… blessed me… and I built for them a permanent Temple. I gathered all their inhabitants and restored their place of residence." This archeological discovery strengthened the view that Cyrus was sympathetic and supportive of all the peoples under his rule and that the Declaration which appeared in the Bible was an accurate reflection of history.
Cyrus was indeed tolerant of other religious beliefs (because it helped keep the conquered peoples in check), but it isn't the case that Cyrus made a special decree unique to the Jews as is claimed in the Bible. The cited inscription, which makes no reference to the Jews, indicates that Cyrus had a temple built in honour of Marduk (to placate the conquered Babylonians), and he allowed other peoples captured by Babylon to restore their homeland. There is no indication (nor reason) that Cyrus would have a temple built in honour of Marduk in Jerusalem, which would in any case be inconsistent with his religious tolerance.