My dissertation assesses the responses of indigenous societies in Sicily and Sardinia to Greek and Phoenician colonial religion in the eighth through fourth centuries BCE. Since the 1980s, scholars have generally downplayed Greek cultural influence on indigenous populations, reacting against traditional “Hellenization” models. This reaction has set up an intellectual dichotomy between postcolonial and Hellenization theories, creating an increasingly stagnant debate. I address these problems by conducting a rigorous comparative study of religious practices among Greek, Phoenician, and indigenous societies. I argue that while indigenous communities integrated Greek-style material culture and practices into their religious lives, they showed much less interest in Phoenician material culture and religion. I explain this contrast in terms of the greater social accessibility and more communal features of Greek polis religion, which were advantageous to native societies in a period of rapid change, and which enabled new levels of Mediterranean-wide, sociopolitical integration.