Christianity in pre-Islamic Arabia

Religion in pre-Islamic Arabia was historically traditional, local polytheistic religions. In the fourth century, Christianity became the dominant religion in the Roman Empire, Armenia, and Ethiopia, and began to make ground among large populations of Roman Arabs across the Sinai Peninsula, Jordan, southern Syria, and in the interior of the Arabian Peninsula, where large populations of Arab Christians emerged.

Source: Wikipedia — Christianity in pre-Islamic Arabia (CC BY-SA 4.0)