The purpose of this dissertation is to write a history of the reign of Nabonidus (Nabu-na'id), the last king of the Neo-Babylonian dynasty, which presided over the destinies of the Near East from 626 to 539 B.C. The period covered here extends from 556, when Nabonidus was elevated to kingship as the result of the conspiracy to usurp the Babylonian throne, to 539 B.C., when Cyrus, the founder of the Persian empire, succeeded in conquering the Neo-Babylonian kingdom, thus bringing about the downfall of the last native Mesopotamian state.

The cuneiform sources for the period under consideration fall into three categories: monumental texts (royal inscriptions), literary texts (chronicles and historical-literary compositions), and archival texts (nearly 3000 published and unpublished administrative documents dated to the reign of Nabonidus). The methodology used consists of confronting the evidence from these three categories of sources, a procedure which most previous studies of the reign of Nabonidus have failed to follow.

The main conclusion which emerges from evaluation of these sources is that the reign of Nabonidus should be divided into three distinct periods. The early years (556-553), a period in which Nabonidus strove to present himself as the restorer of Babylonian prestige, both at the domestic and international levels. The Teima period (553-543), when, as the result of a political crisis, the king set out on a military campaign to Arabia and took up residence in the oasis of Teima for ten years, entrusting his son Belshazzar (Bel-sar-usur) with regal power in Babylonia. The last years (543-539), a period in which Nabonidus, after having returned to Babylon, tried to impose a religious reform which aimed at promoting the moon god Sin to the head of the Babylonian pantheon.