Religious conditions of Arabians before the advent of Islam?

Answer 1

Islam originated in the mountainous southern Arabian Peninsula. Before the advent of Islam, the dominant religion was Christian, with smaller numbers of Jews and pagans. Arab paganism focussed on worship at the Ka'bah, now believed to have been built by the Prophet Abraham. Most of the numerous pagan deities were associated with natural objects, stones and stars.

Officially, the Ka'bah was dedicated to Hubal, a Nabatean deity, and there were 360 idols, tokens of all the clans, arranged around the Kabah, but by the time of the Prophet Muhammad, it seems the Ka'bah was venerated as the shrine of Al-lah, the High God.

Answer 2

Most of Arabs were Henotheists that means they were believing in Allah (the Creator) but worshiping idols as partners to Allah, claiming that they bring them closer to Allah. There were some minorities believing in Christianity and Judaism.

These idols had names as Aglibol, Atargatis, Hubal, Ishtar, Al-Uzza, Al-Manat, Al-Lat, Wadd, Bes (same as Egyptian Bast), Bel Shamen, Abgal, Astarte, Nergal etc. As you can see one difference is that Islam is purely monotheistic whilst Arabian paganism is henotheistic. Another difference is that using pictures to depict God is totally forbidden in Islam whilst it was common place in pagan Arabia.