This study investigates the functions of the Mesopotamian goddess Ištar in pre-Sargonid Assyrian Royal inscriptions from the reigns of Ititi through Šalmaneser III in an effort to better comprehend how the goddess Ištar came to be the preeminent deity of the late Neo-Assyrian kings. The derived goal is to ascertain whether these functions changed over time and to establish whether any apparent variations were due to the adoption of particular manifestations of the goddess (thus linking innovations/functions to specific hypostases of the goddess), the result of broader theological movements, or merely the result of changes to the literary form of an inscription. Finally, the study asks: can Ištar's functions inform us as to her position in the theology present in the inscriptions, and if so, what was that position?

In order to discern and trace the development of the functions of the various manifestations of Ištar, this study will examine all significant references to Ištar in the corpus. Because the titulary, action unit, concluding formula, and invocation each serve a distinct purpose within an Assyrian royal inscription, this study is divided by these literary units. The results of this study confirm that the central function of Ištar in the corpus is either to ordain or assist in the acquisition and maintenance of an Assyrian ruler's sovereignty; however, if Ištar was ever a deity native to Aššur, the texts do not reveal this status. Instead, under the designations Bēlet Ninua "Sovereign of Nineveh" and bēlet qabli u tāhāzi "Sovereign of Combat and Battle" she was connected, not to southern Mesopotamia as some would argue, but to the north, northeast, and northwest of Aššur. The study also determines that Ištar's rise in power can be linked directly to the rise in stature of Aššur (as it became Assyria) and her kings.

Following the conclusion of this study, are a series of appendices. Each presents an historical survey of each of the designations for Ištar which are present in the invocation units of the inscriptions.