Of the myriad Sumerian deities that have emerged from the cuneiform records of ancient Mesopotamia perhaps the most famous - but least understood - is the goddess Inanna, the' lady of heaven'. As a patron of sexuality and aggression she appears in many ancient myths and legends and continues to exert a fascination over contemporary minds. Southern Mesopotamia, called Sumer, witnessed the development of the world's oldest writing system during the Late Uruk period. However, there are few references to Inanna in the extant cuneiform records before the Dynasty of Akkad. Any reconstruction of the cult of Inanna at the dawn of history must, therefore, rely initially on textual evidence of much later periods: the vast repertoire of myths, hymns and prayers to the goddess have been attributed to the 3rd Dynasty of Ur III and the Isin-Larsa Dynasties. Certain details in these stories may reflect beliefs and practices from earlier periods but, these elements are difficult to identify. However, the archaeological record of the late fourth and third millennia has revealed evidence for numerous temples dedicated to Inanna, testifyingto an important and widespread cult. This paper first discusses the archaeological record, before going on to attempt to define the role of Inanna and investigate a proposed syncretism of the goddess wi th the Semitic deity Ishtar.