Belshazzar (or "Baltasar"; Akkadian "Bel-sarra-usur") was a prince of Babylon, the son of Nabonidus, the last king of Babylon. In the "Book of Daniel" (chapters 5 and 8) of the Jewish Tanakh or Christian Old Testament, Belshazzar is the King of Babylon before the advent of the Medes and Persians. Wikipedia
The definitive Wikipedia entry for Belshazzar. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Belshazzar