Belshazzar (Emperor living at the time of Exile and Return)

Belshazzar ruled Babylon during the exile and appears in the Bible almost entirely in one scene: the night handwriting appeared on the wall of his banquet hall in Daniel 5. Scripture calls him Nebuchadnezzar's son, though cuneiform records identify his real father as Nabonidus, Babylon's last official king, who left Belshazzar running the city for over a decade while he campaigned in Arabia. That same inscription answered a long-standing objection to the book of Daniel: critics had assumed Daniel simply had the wrong king, since ancient king lists never named Belshazzar as ruler, until Babylonian texts turned him up. The Nabonidus cylinders name him as Nabonidus's firstborn son; it is the Verse Account of Nabonidus that has the king entrusting the kingship to him, which is what makes him exactly what Daniel implies, the man actually in charge when the Persians took the city.