Monarchy, in one form or another, is a method of social organization that far predates our emergence into sentience. Any random pack of dogs thrown together will select an alpha dog and proceed about their canine business quite happily. Given that, we can safely assume that as world-organizing concepts go, polytheism and monarchy were the norm for many thousands of years. They probably jostled each others shoulders from time to time, but that was likely about it.
Long about 500 BCE, the lovely city of Athens in Greece came up with a new idea for organizing society called democracy. Athenian democrats (yes, I decided to phrase it that way to poke any Republicans reading this blog) were fairly extreme in their application of the concept. They didn't elect representatives to vote for them, all eligible voters voted on everything! One of my favorite things to point out to patriotic Christian Americans is that their beloved democracy was invented by people who worshipped Zeus, Athena, Apollo, etc. I'm just mean that way.
Anyhoo. While all this was going on in Attica, over in ancient Israel, the followers of Yahweh were doing a pretty fair job of elevating their deity to a supreme position. I suppose I ought to mention that there is extensive documentation of the fact that the pre-Mosaic (and some post) Israelites were polytheistic. That's where most of the exotic-sounding demon names in the Bible come from. Ba'al was the deity of the Yahwist's chief political rivals, so a special place in demonology is reserved for his name.
So now in a human society that was comfortably used to being organized by polytheism and monarchy, we now have competing models. Polytheism versus monotheism, and monarchy versus democracy.
I smell trouble