Jesus in the Talmud
In the first few centuries CE, there were many sects of Judaism (such as Pharisees, Essenes, and Sadducees) each claiming to be the correct faith. Some scholars treat Christianity, during that era, referred to as Early Christianity, as simply one of many sects of Judaism. Some sects wrote polemics advocating their position, and occasionally disparaging rival sects. Some scholars view the depictions of Jesus in the Talmud as a manifestation of those inter-sect rivalries – thus the depictions can be read as polemics by the rabbinic authors of the Talmud which indirectly criticized the rival sect (Christianity), which was growing and becoming more dominant.
Jewish diaspora
During the Middle Ages, due to increasing geographical dispersion and re-settlement, Jews divided into distinct regional groups which today are generally addressed according to two primary geographical groupings: the Ashkenazi of Northern and Eastern Europe, and the Sephardic Jews of Iberia (Spain and Portugal), North Africa and the Middle East. These groups have parallel histories sharing many cultural similarities as well as a series of massacres, persecutions and expulsions, such as the expulsion from Spain in 1492, the expulsion from England in 1290, and the expulsion from Arab countries in 1948–1973. Although the two branches comprise many unique ethno-cultural practices and have links to their local host populations (such as Central Europeans for the Ashkenazim and Hispanics and Arabs for the Sephardim), their shared religion and ancestry, as well as their continuous communication and population transfers, has been responsible for a unified sense of cultural and religious Jewish identity between Sephardim and Ashkenazim from the late Roman period to the present.