During the Hellenistic and Roman periods, Jews established communities in new regions, from Antioch to Alexandria.
The following article is reprinted from Jewish People, Jewish Thought, published by Prentice-Hall.
The first permanent Jewish diaspora was the settlement in Babylon created by Nebuchadnezzar's deportations from Judah in the 590s-580s [BCE]. (The Israelites exiled by the Assyrians in the 720s did not long survive as a separate group.) Although the Babylonian Jews returned to Jerusalem in several waves during the Persian period, a sizeable Jewish population continued to reside in Mesopotamia, and…played an influential role in Jewish intellectual history beginning in the third century CE.
In Egypt, Jewish settlements were established by Jewish soldier contingents brought there by the Persians. These exilic and postexilic communities were a modest prelude to the remarkable expansion in the numbers and distribution of diaspora Jews that occurred in the Hellenistic era
Diasporas were a common feature of the Hellenistic-Roman world. In the fourth century BCE, colonies of Egyptian, Syrian, and Phoenician merchants were frequently in the seaports of Greece and Italy. After the conquests of Alexander the Great, Greeks and Macedonians constituted an immense diaspora throughout the Near East. Ethnic resettlement and religious diffusion went hand in hand, as settlers brought with them ancestral cults and won for their gods new worshippers among the local population. Although not unique, the Jewish diaspora was outstanding in its ability to preserve and perpetuate its identity at considerable distance from the homeland and over large stretches of time.
Several factors guided the spread of the Jewish dispersions in Hellenistic times, of which the political history of the Mediterranean basin was the most important. During Ptolemaic rule of Judea, large-scale Jewish settlement in Egypt began. Under the first Ptolemies, Jewish captives, when freed, established communities throughout the country. The Ptolemies brought in Jewish soldiers and their families, and other Jews migrated from Judea to Egypt probably for economic reasons.
At its height, Egyptian Jewry in Hellenistic time was highly diversified: There were peasants and shepherds, Jewish generals in the Ptolemaic army, and Jewish officials in the civil service and police. At Leontopolis, an Aronide priest form Jerusalem founded a small temple with a sacrificial cult modeled on that of Jerusalem. (The shrine survived for over two centuries until just after 70 CE, but it does not seem to have been an important place of worship for Egyptian Jewry as a whole.)
Alexandria, the capital of the Ptolemies and the intellectual center of Hellenistic civilization, became one of the most populous Jewish communities in the world between the third century BCE and the end of the first century CE, numbering several hundred thousand at least. Alexandrian Jewry included wealthy merchants, bankers, and shippers at one end of the social spectrum and masses of Jewish artisans and shopkeepers at the other. The Ptolemies also founded Jewish colonies in the cities of Cyrenaica (modern-day Libya). The Falashas [or “exiles” in Amharic], black Jews of Ethiopia [who refer to themselves as “Beta Yisrael”, house of Israel], may stem from Egyptian Jewish contacts during Hellenistic and Roman times.