The Abbasid scholar Jāḥiẓ (d. 255 / 868) often provides a bird’s-eye view of topics in the Abbasid period and, luckily for us, he wrote on a ton of topics. In a short treatise rebutting Christians of his day, he gives a description of religion among the Arabs prior to Islam ...
He mentions four religions that pre-date Islam among the Arabs: Christianity (al-naṣrāniyyah), Judaism (al-yahūdiyyah), Magianism (al-majūsiyyah), and what he vaguely calls “the religion of the Arabs”. See the map below to located the places/tribes mentioned ... 
[The map comes from this study of Robin: academia.edu/37672327/_LAra…]
Jāḥiẓ writes: "Christianity gained ground among the Arabs and became prevalent among, except for the tribe of Muḍar. Neither Judaism nor Magiansim [i.e. Zoroastrianism] prevailed among them [i.e. Muḍar], and Christianity had not gained ground among except for a tribe ...
who resided in al-Ḥirah called “al-ʿIbād”. They were Christians, but they were obscure along with those small numbers in some of the tribes. Muḍar recognized only the Arab religion (dīn al-ʿarab), and then Islam...
Christianity prevailed among the Arab kings and their tribes: over Lakhm, Ghassān, al-Ḥārith ibn Kaʿb in Najrān, Quḍāʿah, Ṭayy, and many tribes and well-known clans. Then [Christianity] appeared among Rabīʿah and prevailed among Taghlib, ʿAbd al-Qays, and branches of Bakr ...
and later among Āk Dhī l-Jaddayn especially.
Islam came and Judaism did not prevail over any tribe, except among some people from the Yemenis and small numbers from the entirety of Iyād and Rabīʿah.
Islam came and Judaism did not prevail over any tribe, except among some people from the Yemenis and small numbers from the entirety of Iyād and Rabīʿah.
The greater part of Judaism was in Yathrib, Ḥimyar, Taymāʾ, and Wādī al-Qurā among the descendants of Aaron who were not Arab." Fin
