Thomas E. Gaston discusses the developments in scholarship concerning the authenticity of the book of Daniel and its depiction of Belshazzar.
Thomas E. Gaston, Historical Issues in the Book of Daniel (Paternoster Biblical Monographs; Milton Keynes, U.K.: Paternoster, 2016), 52-64
Belshazzar
The case of Belshazzar is often trumpeted by conservative commentators, and not without reason, as it is one instance (of many) where the Bible has turned out to be historical, contrary to the accusations of some of its critics.
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Summary
Since the nineteenth century critical scholars have been pressed into retreat on the issue of Belshazzar as more evidence and more research is brought to bear on the topic. Though some scholars today still repeat the objections of earlier critics, others dismiss the validity of these arguments. Comments on this issue by P. R. Davies are telling:
It has been clear since 1924 (Montgomery, pp. 66-67) that although Nabonidus was the last king of the neo-Babylonian dynasty. Belshazzar was effectively ruling Babylon. In this respect, then, Daniel is correct. The literal meaning of ‘son’ should not be pressed; even if it might betray a misunderstanding on the part of Daniel, a strong case against Daniel’s historical reliability is not enhanced by the inclusion of weak arguments such as this.
The book of Daniel is shown to be reliable on the issue of Belshazzar and, in fact, superior to the Greek historians who seem to have scanty information about Belshazzar. The author is right to describe Belshazzar as ‘king’ (melek) and correctly understands his position as second in the kingdom. His description of the relationship between Belshazzar and Nebuchadnezzar is perhaps misleading in English translation, yet in Aramaic may preserve some clue to Belshazzar’s maternal-ancestry. If the author is correct regarding the circumstances of Belshazzar’s death—and at present there seems no reason to doubt it—then he preserves intimate knowledge of these events, which are not even recorded in any extant cuneiform text.
Whether or not readers accept the miraculous events recorded in Daniel 5, the author has shown himself a capable and informed narrator and his testimony is worthy of the attention of historians.