From what I know of Islam they keep talking about how the populace before Islam was full of 'pagans', and that the Kaaba was a holy building to them too, filled with idols and statues. What were those statues of? Did they have a pantheon type thing too? Do we know of it?

Also as a follow up question, in terms of Christianity people keep talking about how it kinda assimilated the smaller religions it came across and we can see it in the modern religion, with easter and christmas and whatnot being based off pagan holidays. Is that something we can see in Islam too?