A useful way to think about the history and pre-history of Europe and West Asia since the Last Glacial Maximum is to frame it as a matter of techno-linguistic-cultural waves and layers.
The earliest layer is that of European, Levantine, and Caucasian hunter-gatherers, who are quite distinct and segregated populations from each other and not merely gradual clines of different degrees of genetic admixture. Prior to the Neolithic Revolution, Caucasian hunter-gathers and Levantine hunter-gathers were as distinctively different from each other (or more so) than an Irishman is from a man in China today, at a distance of a few hundred miles from each other or less, and while there was admixture during and after the Fertile Crescent Neolithic Revolution, the populations remained very genetically distinct until the Bronze Age, and remain distinguishable, genetically, even today.
Hunter-gather cultures in Anatolia and the Levant are just on the verge of transitioning to becoming Neolithic farmer cultures in sites like Göbekli Tepe and signs of proto-farming in the Levant, when the Younger Dryas climate event hits and postpones that breakthrough for a few thousand years after these false starts, until you get the Fertile Crescent Neolithic revolution.
The Fertile Crescent Neolithic Revolution collects crops and animals, which are native to different parts of the Fertile Crescent, to domesticate and then combined them into a Fertile Crescent Neolithic package over a few centuries (that was tweaked somewhat with a few more domesticated plants and animals in each direction it expanded , like the donkey added in Egypt and a few more crops in Greece and the Balkans), but still not fully merging ethnically (and probably not linguistically either) and instead remaining ethnically distinct first farmer cultures and populations.
The group of first farmers derived from an ethnicity known in ancient DNA circles as Caucasian hunter-gatherers heads east to bring herding and farming into West Asia.
The group of first farmers in the Levant heads south to bring herding and farming into Egypt, Ethiopia, and the rest of North Africa. This branch can be associated with the Afro-Asiatic languages, although whether the Afro-Asiatic languages originated in the Neolithic Levant, or were a back reaction from some Northeast African hunter-gatherer language that dominated culturally over the original Levantine farmers and then expanded back to North Africa and the Levant from perhaps Ethiopia or upper Egypt, is hard to know.
The group of first farmers in Western Anatolia expands in two waves that split off from the same source West into Europe: the Linear Pottery Neolithic (LBK) farmers more or less to the north along central and eastern Europe's great rivers, and the Cardial Pottery (CP) farmers more or less along the northern coast of the Mediterranean. The archaeological record also suggest that the LBK farmers in turn had a fairly basal split into two distinct branches with different material culture traditions. Probably each of the three major components of the Western Anatolian first farmer traditions spoke different, related languages within a Western Anatolian first farmer language family.
As these first farmers expanded into the more agriculturally suitable areas that they encountered, they did so primarily as families that largely replaced the much more thinly populated existing hunter-gather populations (in many cases, the population density of farmers was as much as a hundred times greater than the hunter-gathers who had preceded them in the area and the farmers were also much more prone to stand their ground to protect their crops than to migrate away although early herders were more flexible and hunter-gathers transitioned to herding more easily than they transitioned to farming), although a small number of locals were integrated into each expanding first farmer population, mostly women taken as brides by first farmer men.
In most of Europe, societies in cultural continuity with these first farmers start to collapse. Maybe its due to unsustainable agricultural practices, maybe its due to natural climate changes. In the earlier stages of this decline, there is some introgression of people who were part of remaining European hunter-gather cultures (sometimes partially adopting herding), who had continued to persist in places unsuitable for Neolithic farming, mostly women, and some first farmer communities revert to herding and hunting and gathering almost entirely, largely abandoning farming.
A few places, like Sumerian, Egyptian, and highlands West Asian societies, that were some of the earliest adopters of the Fertile Crescent Neolithic Revolution start to innovate and adopt early metallurgy, proto-writing or a true written language, and larger scale political and social organizations with kings and high priests who are more than just chiefs and shamans of small tribes or bands. They ran kingdoms and established full fledged bureaucratically organized religious institutions.
The ergative language speaking linguistic groups of the highlands of Anatolia, the Zargos mountains, and the Caucasus mountains, and of Mesopotamia constitute one group of early metal age societies which emerged in specific communities that used their technological advantages of conquer societies that were stuck in the Neolithic farming era and didn't adopt as fast. These specific communities probably emerged from an ergative language first farmer society.
The Ancient Egyptians were another early adopter of metal age technologies whose military, economic, and cultural influence spread its non-ergative language Afro-Asiatic substrate across an ergative language first farmer substrate that extended, at least, to parts of North Africa, either via the Southern coast of the Mediterranean, or via Iberia.
The Harappan culture in the Indus River Valley and Northeast India is a third early adopter of technological advances of Copper Age technology that manages, somehow, to become dominant with much division or warfare.
Meanwhile, Pontic Caspian steppe hunter-gathers who had adopted herding and domesticated the horse, and made advances in making practical use of simple animal pulled wheeled vehicles enjoyed a fruitful synthesis with nearby West Anatolian derived first farmers from the LBK branch of their expansion into Europe, probably in Sredny Stog, that gave rise to the first proto-Indo-Europeans. Maybe the farmers had early metallurgy already, maybe the herders borrowed it from neighboring societies like the Caucasians, or maybe it arose independently not long after the synthesis that created proto-Indo-European society. But, the Indo-Europeans were already a society of Bronze Age horsemen and charioteers before their main expansion. One of the earliest expansions from this PIE core is east into the Tarim Basin where they become the Tocharians.
When a large area arid climate event strikes West and South Eurasia from Ireland to the Middle East and North Africa to Harappan territory in South Asia, in a time frame that peaks around 2500 BCE to 1500 BCE with climate leading its impacts on the affected societies, societies that were still Neolithic farming societies or were less advanced entirely collapse, while societies that had advanced to the copper age or very early Bronze Age are weakened and vulnerable to conquest, but don't actually collapse.
Indo-Europeans expand in all directions into the vacuum as the climate event strains existing cultures. In most places that had not reached the metal age when this happened and had almost fully collapsed, the Indo-Europeans almost fully wiped out existing hunter-gather and first farmer men, while assimilating some of the women from the existing culture, in patriarchal clans. This was the story for the Corded Ware Culture, more or less in central and eastern Europe, and the story of the Bell Beaker culture invaders of Great Britain and Ireland.
In places where early metal age cultures were still standing and just weakened when they arrived, like the Harappan culture of South Asia that gave rise to Sanskrit speaking Indo-Aryan society (that briefly extended as far as the Mittani empire at the Hittite Empire's border, before it was replaced by the Indo-Iranian Zoroastrian culture), the Hattic culture of Anatolia which came to be ruled by the Hittites, and the Aegean (where they conquered the Greeks and Hattic-related Minoans but adopted considerable parts of local language and culture), and Basque Country (it isn't entirely clear if this is a first farmer society remnant or if it was a distant and first farmer substrate influenced far outpost of early metal aged culture, probably the latter), there was more give and take, with a greater substrate influence on the conqueror's language through substrate influence, on the conqueror's religious beliefs and identity, and other deep rooted aspects of local culture (like Harappan curry). Isolating geography in Sardinia, and in the highlands of the Italian Peninsula's Etruscans and the Alpine kin, and in the highlands of Basque country (possibly assisted by its cluster of RH negative blood types) resisted longer and were changed less by the Indo-Europeans, although most ultimately fell to them, aided by somewhat less collapsed societies with somewhat more advanced early metal aged cultures (and by adopting technologies from the Indo-Europeans who sought to conquer them).
Indo-European expansion wasn't unchecked, however. The Afro-Asiatic cultures of the Levant and Egypt managed to resist them as did Mesopotamia, which Afro-Asiatic people had conquered from the Sumerians before this collapse. Geography prevented them from expanding past the Tarim Basin into East Asia and Central Asia. In Europe's far Northeast, as far as what is now Finland, northern Sweden, the Baltic states, and much of what is now Russia, as well as (much later) Hungary, Uralic people arrived as a post-Indo-European layer, or arrived to replace hunter-gather-fishing populations that the Indo-Europeans either never reached or didn't manage to hold onto for very long.
Then, another climate event triggered Bronze Age collapse around 1200 BCE. This only slightly unsettles the division of the world between Indo-European societies and Afro-Asiatic ones, for example, with the migration of Mycenaean Greek sea people into the Southern Levant after being fended off by more robust Egypt, to become the Philistines.
During Bronze Age collapse and its immediate aftermath, the waves of migration and war in Europe and West Asia become intramural fights between Indo-European people beyond the standoff between the Bell Beaker Indo-Europeans in Western Europe (known for their archery) and their successors, and the Corded Ware people to their east in Europe and their successors (know for their battle axes), whose respective territories shifted only a little (most notably midway through the Bronze Age in the vicinity of Denmark) from about 2000 BCE to 1200 BCE.
As Bronze Age collapse struck, Anatolian Indo-Europeans and Greek Indo-Europeans fought the Trojan War until it all collapsed into the Greek Dark Ages. Around that time that the Greek dark ages ended and classical Greek civilization started to emerge, Celtic peoples expanded from somewhere around Czechia as far west as Ireland and as far southeast as Anatolia. As Europe and West Asia emerged from the dark ages, the Iron Age technologies that the Hittites has managed to prevent its neighbors from acquiring prior to Bronze Age collapse, became ubiquitous. Iron wasn't actually a superior metal for weapons to bronze, but it was easier to mass produce and almost as good (and in isolated communities in what is now Iran, high quality steel far superior to bronze or iron was invented, around 1000 BCE, only to be lost centuries later before it could be adopted by the Roman Empire or the Islamic Empire).
The Iron Age was followed by Greco-Roman classical civilization eventually leading to Greek conquests of West Asia up to India (only to ultimately lose most of this territory one way or another in several big installments), and to the Roman Empire at its peak that reached Hadrian's Wall in Britain, Romania, the Levant, Egypt, North Africa, Southern Europe, and Anatolia. This lasted until another climate event led to the Western Roman Empire's collapse. A century after Rome collapsed, the Islamic empire expanded into vast swaths of territory in North Africa, Southwest and West Asia, Iberia, Malta, and the Balkans and beyond into South Asia and Southeast Asia and the Sahel, while the Christian Byzantine empire held on for several more centuries as it gradually lost territory, until it fell entirely to what had morphed in several rounds of Islamic regime changes into an Ottoman Empire that absorbed and coopted into Islam, Turkic invaders with origins in Southeast Asia, with the little interruption of the Mongol Empire along the way.
While the Islamic empire expanded, non-Muslim Europe collapsed with Germanic, Slavic, and Uralic tribes roaming about Europe in the migration period (giving rise to Hungary whose Magyar rulers swiftly converted from being pagans to Christians), Charlemagne and feudal lords running Europe in a fig leaf of a Holy Roman Empire under the Pope and launching several largely futile Crusades into the Levant, Viking raiders plundered Europe and briefly settled in North American only to collapse there and retreat (one branch of Vikings became the founding dynasty of and rulers of Russia's slavs), the Mongol Empire spanning from Persia to Korea before collapsing in the 13th century, multiple waves of the Black Plague ravaging Europe from its source in the east, missionaries re-Christianizing Europe from Ireland to the east until the last pagans of Europe are in the Urals and almost everyone else has nominally become Catholic by the late 11th century CE, and monastic orders doing what they could to preserve classical civilization for the thousand years of the Middle Ages that ended with the Columbian Exchange as Iberians and other Europeans colonized the Americas, with the Renaissance that finally restored classical Roman levels of technology and social order, with the Protestant Reformation, and with the end of the Reconquest of Iberia from the Moors. I'll end this survey with the start of this early modern period around 1500 CE.
Now, I'm writing this post from memory, which is partially why I've left out some things, particularly in West Asia and the details in far Northeast Europe and North Asia. I've omitted the stories of the Armenians, the Kurds, and the Druze. I skipped the process by which the Sumerian language was replaced by a succession of Semitic languages in Southwest Asia and Mesopotamia's trade ties to the Indus Valley Civilization and the eastern coast of Africa. I haven't adequately covered the history of the Caucuses. I've left out the fairly well understood history of the Jewish people after the fall of the Second Temple around 70 CE and haven't said enough about the Phoenicians and the Punic people. I haven't discussed the rise of Christianity during the Roman Empire or the demise of Zoroastrianism and polytheistic paganism. I haven't explored the connections between the Jewish, Christian and Muslim accounts of Southwest Asia's history through the legendary histories of their holy texts and the historical realities. Nor have I discussed why the Bronze Age is so full of what I call "legendary history" that is a mix of fiction and fact in purportedly fictional accounts that is so predominant across cultures in this era. I've left out the expansion around the time of the domestication of the camel that gave rise to the Berber people. I've barely touched on the repopulation of Europe by hunter-gathers from basically three refuges after the Last Glacial Maximum. I haven't mentioned the Silk Road or the history of Central Asia before and after the Mongols. I didn't cover how pottery made its way from the coasts of China and Japan about 16,000 years ago, over thousands of year to produce the transition from the pre-pottery Neolithic in the Levant to the pottery Neolithic of Europe and the Levant, or how the Black Plague got to Europe. I omitted the trans-Saharan slave trade, and Roman, Greek, Egyptian, Anatolian, Germanic and Viking slavery practices.
But the point isn't to cover all of the details. That would take a book, not a blog post. It is to provide an overarching framework into which the details can fit and be better understood. And, of course, this post only minimally touches upon history and pre-history become its title's West Eurasian scope, even though there was lots going on in the rest of the world which is much less well known. Africa, for example, didn't start to fall decisively behind the rest of the world technologically and economically until perhaps five or six hundred years ago, and it took quite a while before the gaps became as stark as they are today (a process that only really started in earnest around the time of the trans-Atlantic slave trade that started after the time period covered by this post).
Actually, to be honest, I'd started trying to frame the issues presented by the origins, cultures, and linguistic history of Greece, West Asia and Southwest Asia up through the early Iron Age, and ended up going a little further afield with a forward outlining Western Civilization from its earliest roots which would be about ten pages in print. I did touch on that and frame it in a narrative (admittedly one that is sometimes hotly contested by legitimate academics even in the present). But, I can refocus on that in a more detailed and referenced manner in a future post.
