... I also have a dislike for the idea of "chosen" people. Fatalism and predestination in the divine scheme of things just don't appeal to me at all ...It occurred to me that many religious/theologic constructs tend to proclaim in some form or fashion that those who have complete faith and give total buy in to a particular religion will gain favor and blessing from eternal bliss in heaven to 72 virgins (I don't think it's specified as to which gender said virgins possess so ... ) and so on et. al. Anyway, I got to thinking that earlier religions had an ever growing cadre of task specific gods that handled particular issues and as more issues arose, more gods were created to address them ... I can see how such a convoluted and unwieldy org chart of deities could rapidly become confusing not to mention expensive in the form of proper offerings to curry favor with the specific god that handled your specific needs at a give time.
It seems that after a pretty good run, the polytheistic religions started to lose favor and followers as new religions with more streamlined customer support were implemented. Certain tribes - perhaps simply because they were excluded from participating in specific religions due to race, status, nationality etc. - may have simply developed their own version of the best gods from the polytheistic religions and tailored their new god's requirements to their own customs and means.
And of you're going to tailor make a god, you may as well dress it up to the nines and give it powers that surpass that of your oppressors gods, right? In a world during a time when human knowledge of the natural world was rudimentary, gods "just had" to be the source and cause for things like earthquakes, lighting, shooting stars, diseases etc. And why have many gods that handle individual issues when you can make one that handles multiple issues ... and if this god were powerful enough to take on all these takes ... maybe they could use that "power" to intimidate foes in other tribes/lands.
Much like how weapons began their development, so too did these theologies/religions morph into more refined, more powerful more all encompassing dogmas. As the generations tick by, each new generation refined, detailed and perfected their religion ... just like how the world went from mortars to conventional bombs and ultimately to the A-bomb and then to ICBMs delivering multiple warheads.
Back then, there was no such awesome man made power - but there were existing religions, but they didn't quite fit everyone's needs so some made new gods/religions to fill those needs ... they changed the structure ... instead of one problem, one god ... why not one god, many problems addressed - provided you yous the proper rite, incantation, prayer etc. to invoke your god to help ... a real one size fits all deal that is easier to deal with because it's streamlined and efficient and you can go to one temple to do your theological laundry ... a real on stop shop.
It's no small wonder it caught on. And since you didn't have to spread your wealth around to many gods/temples, you'd have more resources available to conquer your enemies and slaughter and subjugate them like they had once done to you. So the religions with the most efficient "requirements" that allowed to to pay your respects, make your offerings and get down to the taks of slaughtering foes with the least daily interruptions were are the religions that ultimately became what we have today in the world.
The only difference is, now we really don't even need them because we have a real good grasp on how the natural world works ... so either some religions will reinvent themselves (notice how Pope Francis is changing doctrine to fit the demands of modern world) ... and some will just eventually dwindle and wither down to obscure, archaic footnotes to history ... just like muzzle loading muskets.
So yeah, I think religions started as a way to explain the (then) unexplained (which we, of course, now know) and morphed into a "My god(s) is/are bigger and more powerful than your god(s) ... just like an arms race ... and who wants to cross the biggest most powerfulestest deity?
Bring on the "arms" reduction treaties ... and soon, please