Himyarite Kingdom
Before the advent of Islam, it appears from indications in the Qur'an it would appear that the Jews to the West of the Himyarite Kingdom, in western Arabia, maintained some form of rabbinical organisation, possibly connected to late antique Judaism, and were not wholly cut off from their brethren elsewhere in the Middle East. One source speaks of rabbis from Tiberias itself enjoying the hospitality of Dhu Nuwas's court. The apparent conversion of local Himyarite rulers to Judaism, or some form of a Judaic monotheism, as early as the late fourth century under the Tabbāi'a dynasty, is indirect evidence that suggests that effective Jewish proselytization was active in the region.