Origins of Europe, or, why Europeans aren't Asians, which is a good question to ask.
Europe, or Europeans, have been called a "People without a history". They rose without many connections to the large classical civilizations which surrounded Europe proper and preserved the sort of parochialness which came from that, to the detriment of the world as it turned out.
You look at Asian cultures and there's a sort of continuum which exists: the Persians can understand the Arabs and both can understand the Indians and all can understand the Chinese. Much different civilizations. Oh, and the Turks can understand all of the above as well.
Different civilizations, different ways of looking at the world, different social orders, but nonetheless they shared, and share, a common language for understanding which the Europeans did not, and do not, have access to.
The civilizations outlined above, with the addition of further off territories in East Africa and Southeast Asia, made up the core of the ancient world.
But Europe wasn't privy to it.
There's nothing that would have prevented the Europeans from sharing a common worldview and becoming part of the "pax ancienis", as I'll call it, but nevertheless they did not.
I think that the answer lies in the continual social instability of Europe during the times when these great civilizations flourished in their classical forms.
Greece offers a good example of this: the Greeks invaded present day Greece and found an Asian civilization, the Minoans, there and they acculturated to them eventually founding a hybrid civilization called the Myceneans.
The Myceneans civilization was in turn destroyed by further invasions of tribes people from the north, ending the first European experiment in the type of social order which the ancient world was based on: the large scale state.
After this state fragmented into bits Greece reverted to tribal rule somewhat modified by the legacy of the Myceneans, much like the Germans after they overran Rome, and eventually evolved into still primitive city states.
The city states prospered but were still tribal groups. When the biggest large scale State in the area expanded into Greece the tribespeople rebelled and won. The power was Persia.
By the time of the Persian wars the Greek way of life was pretty much set, and it wasn't in the cast that the pax ancienis knew but simply that of a modified tribe system, which refined its political theory and organization but was still primitive.
So by the destruction of the Mycenean state Europe was closed off from the world of ancient statist politics for the reason that beyond the eastern mediterranian, to the west, there were no large state powers to offer contact or culture to Europeans.
But then there's the question of the influence of West African large scale social organization on western Europe, but that's a different story.
Anyways Europe destroyed its opportunity to merge with the civilized ancient world because of the extreme social instability of the society which existed there due to the complete tribal nature of the Europeans.
And the Europeans weren't even native to Europe. They overran people who were related to the present day Finns, Estonians, Kerelians, and Hungarians, who may, ironically, be the native peoples of Europe subjugated in their own lands.
An African presence in Ireland, Spain, Portugal, and maybe even England is likely as well. The Fomorians of Irish myth may have been Africans, and the "black Irish" may be their descendents.
To the East there were no direct civilizations...just the steppes, which did eventually lead to the subjugation of Russia to the Golden Horde, the modern day Kazakhs of Kazakhstan, who proceeded to rule Russia along Mongolian lines...but mainly nothing came of the north eastern frontier of Europe.
But what of the vaunted Indo-European mythological traditions and the social traditions that supposedly came from that?
I think that the Indo-European mythological traditions, which may be expanded considerably to include the Indian and the Persian mythological and religious systems, are the traditions of a pastoral people that happened to have made it in several different empires, with the Europeans proper sort of relaxing in their golden blaze and getting a vicarious kick out of having their pagan belief systems be similar to the Persians and the Indians.
I think that the Indo-European mythological system is basically equivalent with the Turkish one in terms of type with the difference being that the Turks didn't take over India and the Middle East, and their distant cousins didn't take over Europe. There but for fortune we'd be analyzing the structure and weave of the great Turko-Mongolian mythological system and religious belief system instead of the Indo-European one and would be marvelling at how us Anatolians had a culture similar to that of the great Uzbek nation and the Mongolian empire to the East. And we'd be trying to figure out how the differences in culture between the Turks and the Native Americans caused genocide during the colonization of the New World.
I don't think there's a qualitative difference between the proto-indo-european culture and any of the other nomadic cultures which have developed extensive religious literature.