What was the religion of the arad traders?

Answer 1

If you mean arab traders then the answer is: in pre-Islamic Arabia, the arab population was moslty pagan, with a few exceptions. The city of Medina was home to Arabian Jews, and, in Mecca, at the Kaaba their were hundreds of pagan idols as well as a statue of Jesus Christ and his mother Mary which meant that there were some Christians. However once the Prophet Muhammad(peace be upon him) established Islam the pagans either converted to Islam or were killed and in the course of 100 years or so most if not all of Arabia was Islamic.