If participation in church activities is critical for the strength or weakness of religion, there is no denying that Europe comes off poorly. According to American sociologists of religion the rise of religious pluralism in the USA was due to the strict separation between state and church; it compelled congregations and denominations to compete for believers. The European case is different. Here the diversity of religions existed long before the modern period. Since its ancient beginning European culture sought its authorities outside its geographical confines. Greeks and Jews, Hellenism and Hebraism, Athens and Jerusalem, later Mecca and Islam became cultural points of orientation for people living in Europe. The article addresses the cultural and social processes that transformed these and other foreign religious traditions into typical European manifestations: the Roman legal system turned foreign religions into legal categories; it was modernization that led to the articulation of distinctly religious meanings of history and of nature; and it was the detachment from the church that provided the impetus for new societal forms of religion. Those processes are at the center of the European plurality and diversity of religions.