The conquests of Alexander of Macedon radically expanded the horizons of the eastern Mediterranean and Near East, inaugurating an era paradoxically marked by the increased interpenetration of different cultures and the cultivation of self-conscious particularism within these same cultures. Although Alexander's empire soon fragmented, the scope of his conquests sketched the boundaries of a new world. In the following centuries, Hellenistic, Roman, Sassanian, and Byzantine rulers would attempt to conquer and administer parts of this domain, and members of subject nations would circulate through it with increased ease, distributing economic goods and religious knowledge along its trade routes.

Cross-cultural contact was hardly unprecedented. New, however, was the emergence of a common cultural landscape and the growing sense – whether positive or negative – of living in a single oikoumene. Scholars have traditionally focused on the “hellenization” of conquered nations, but the “orientalization” of Graeco–Roman society was no less significant in shaping the culture of Late Antiquity. Moreover, both trends continued to be characterized by the dynamic interplay between acculturation and anxiety about acculturation. Among conquered nations, we find zealous attempts to guard ancient traditions against perceived threats of contamination, alongside enthusiastic efforts to embrace a cosmopolitan identity, with all the economic benefits and social status that came with it. In turn, the “alien wisdom” of Egyptians, Babylonians, Persians, and Jews attracted many Greek and Roman thinkers, and their fascination with the foreign facilitated innovations in religion, philosophy, science, and “magic,” thereby birthing traditions with uniquely late antique pedigrees.