It is generally accepted that throughout the ancient world, religion played an important role in the Greek society and was intricately connected with every aspect of everyday life, public – social and private. The cultic practices and attitudes illustrate a religious system common to all Greeks. In this context, Zeus as father of gods and mortals, was the Supreme of Gods in the Greek pantheon, who was worshiped in every part of the Greek world, bearing a variety of epithets, invocations and different roles, many of which penetrated and became popular into the Black Sea coast colonies as well. The available data on his cult in Black Sea are fragmentary, scattered or unpublished. The aim of the present thesis is to present an overview of the cults of Zeus in the Black Sea region, from the archaic to the roman period, an issue that has never been studied so far comprehensively by scholars and bring into light not only cultic but also economic and political aspects. In this context, literary written sources, inscriptions and archaeological finds from the Greek cities of the Black Sea region referring to Zeus’ cults will be examined and a comprehensive review will be presented. As in homeland Greece, where the god’s cults exhibited both private and official/public character, in the Greek settlements of the Black Sea, Zeus was worshiped by simple citizen and farmers, having a central role in family and domestic life as well as by the official authorities of the state, which built altars, monuments and temples dedicated to him or organized festivals and rituals in his honor. In particular, with regard to his private cults he was considered to control natural and meteorological phenomena, but exhibited chthonic properties as well, that linked him with the fertility of nature, patron of human life and health, averter from evil, savior and guarantor of recovery in times of crisis. These functions are more evident in the southern and western and to a lesser degree in the northern Black Sea coast. On the other hand, Zeus was considered as patron of local communities, cities and districts having defensive, protective and apotropaic attributes, such as in mainland Greece area (e.g. Polieus, Soter, Strategos, Basileus, Eleutherios, Nikephoros, Stratios, Poliarchis, Genarchis, Pyleios, Agoraios etc.) mostly in the 8 southern, to a lesser degree in the northern and least in the western Black Sea coasts, as it is exhibited by coins, rituals and festivals. In the southern Black Sea coast, various epithets associated with Zeus’ local cults, are derived in many instances from local toponyms, confirming the god as patron of villages, small towns and ethnic communities. Moreover, the cult of Zeus was the basis of the precondition for creating a more widespread cult that of Zeus Stratios (Ζεύς Στράτιος), i.e. the army leader, the official royal cult of the Mithridatic kingdom. However, the research conducted on the religious life in the Black Sea during antiquity is limited and the available literature, especially the western one, is insufficient. Although, some publications on the subject written in Russian or in other Slavic languages exist, these have not been translated into more accessible European languages and much of the archaeological material found in the region is still unpublished. As a result, the research on Black Sea religious life in general and in particular the study of Zeus’ cults, remains a daunting task for classical scholarship.