As an aspiring occultist, I want to know the political implications of it.
		
		
	 
I am gonna go back to the beginning here. The original dispute between Baal vs El goes back to Canaanite tribal days. (Hebrews are the same as the Canaanites until Iron Age period I. But they derived from them and the language is a dialect of Canaanite. Any claims they are 
not the same is political propaganda from the bible. Archaeology has shown they were from those people.) El was the top god of the pantheon, he had two wives [Asherah and Anath] and many children. (Think the god Zeus) Baal was one of these kids, but a war god though. (Think the god Mars) The tribes contention started with later people wanted to replace El with Baal. (Though I heard one theory that the "Baal" cults may be the spirit Baals rather than the god, in the bible. I cannot confirm this.)
El was an independent deity of another god, Yahweh, whose origins remain mysterious insofar because it is hard to do archeology in those regions without being shot at. But was merged with El later in Israel. (His origins seem to stem from outside of Israel, 
however.) Yahweh is a god of war. This adds a new layer to El's myths.
I don't think they had a problem with polytheism, until
 later. Originally, it was idolatry. (There are Canaanite statues of El,
 by the way.) Looking at earlier passages in the bible I think they're actually 
henotheistic, which is a type of polytheism
. There's several passages that confirm the existences of other gods, and some don't even attack them. The Prophet Elijah challenges the priests of the god Baal to a duel with whose god is better, Yahweh or Baal.  Elijah was 
not accusing them of abandoning El for other gods. But rather for dividing the attention among them 
both, for example
. Meaning he believed that Baal AND Asherah, existed alongside El.
The goddess Asherah had priests in attendance of this fiasco with Elijah. Not once does Elijah condemn them or her worship. Only Baal's. His tolerance indicates that Asherah, in that time period, an inevitable and tolerable female counterpart to El. [
From The Hebrew Goddess by R.Patai 3rd enlarged edition; Chapter on Asherah] There's also evidence of some type of monotheism in Yahwehist priesthood but not amongst the lay people or in the folk religion, which is probably the spill over most people talk about. 
Around the time of Isaiah they start getting monotheistic and the influence of Zoroastrianism, which had a book, prophet who preached against idolatry, and the old religion. It was the first to do so, not the bible, contrary to popular belief. Originally Zoroastrianism was duotheistic, believing in one good god and one evil one, but it, too, evolved into monotheism. For a longer explanation there is 
. 
So, they started from railing against idolatry for diminishing the importance of Yahweh to attacking all of polytheism during political turmoil when Israel was capture by Babylon and beyond.
Christians started out as a subsect of Judaism. It's in the earliest Roman records. It appears in the NT Jesus still practices Judaism. (Celebrating Passover) It is most likely Jesus was simply trying to reform Judaism not found Christianity. Ancient Christians split over either staying as close to Judaism as possible or doing the opposite/own thing. Guess which sect won? 
This kind of back and forth will go on ad infinitum between the Christian sects to the modern day. I am not a super expert on this part of Christianity, so be kind if I make a mistake here. The gist is there was that Christians wanted political power and unite Rome or something. There was a lot of things going on there. Christians vs pagans, Christians vs each other. No one could agree. Anyway, they merely copied what was already in the bible and its interpretations by their day about monotheism and polytheism.
Islam is related to the Canaanites, as Arabic tribes stem from them and Allah is cognate El. Their "pagan" religion was very different in some areas but also the same to the Israelite/Canaanite one. I believe that Mohammod, and this now is just a
 personal opinion, created Islam to unite the Arabic tribes. Hence Mecca having connections to their tribal days and Islam requiring it of every Muslim. He did this by using the techniques and beliefs from the OT, and eliminating polytheism. Monotheism is a tool here, to help them unite. I also believe some earlier pagans and Christians used monotheism for this reason. (
)