Diaspora: The
dispersion of an originally homogenous people, language or culture.
From Indo-European sper
-- to scatter, to sow.
In the fifth millenium B.C., the Indo-European community was well-organized, had mastered agriculture and animal husbandry, and were mounted on horses and wagons. They began their great scattering. They certainly weren't aware that some day their tribal language would splinter into over a hundred languages, circle the globe, and be spoken and read by people in places they couldn't possibly imagine -- people like us, right now.
Indo-European agricultural productivity most likely created
a population explosion. The population pressure certainly played a part in
compelling the Indo-Europeans to migrate in successive waves to fertile areas
not yet cultivated.
The first group of the migrants to break away -- the Anatolian tribe -- invaded Anatolia (modern Turkey) around 2000 B.C. and established the Hittite kingdom, which held all of Anatolia in its power by 1400 B.C. The Hittite language was the first of the Indo-European languages to find its way into writing. followed by its sister languages Luvian and Palaic.
The Tocharian tribe also diverged from the Indo-Europeans quite early and migrated all the way to the borders of China. Tocharian is one of the more recently discovered Indo-European languages, first recognized in the early decades of the 20th century in texts from Chinese Turkestan. (Curiously, of all the Indo-European languages, Tocharian most resembles the Celtic languages.)
The major portion of the Indo-European community remained in place after the Anatolian and Tocharian tribes had left. From that community came the languages that persisted into written history. The first to branch off were the Greek, Armenian, and Indo-lranian tribes. They must have begun to do so no later than 4000 B.C. because by 2500 B.C., the community was already dividing into two groups, namely, the Indo-lranian and the Greek-Armenian.
By 1500 B.C. the Indo-lranian group had begun to divide into ancient Iranian and ancient Indic. The Iranians settled in the highlands of the Zagros mountains and on into present-day Afghanistan. The Indics (or Aryans) took a path across the Hindu Kush mountains into the Indus Valley. Their dialect, ancient Vedic Sanskrit, is the source from which the historical languages of India are descended. The indigenous peoples of the Indus Valley, known from the archaeological discoveries at their capital Mohenjo-Daro, were apparently displaced by the Indic-Aryans.
Meanwhile, Cretan Mycenaean texts from this same era tumed out to be in a previously unknown dialect of Greek. The Greek tribe had gone its separate way from the Armenians, and had crossed Anatolia south of the Black Sea into Europe. (The myth of Jason and the Argonauts, searching the Black Sea for the Golden Fleece, may be a tale of the Greeks looking for their ancient homeland.)
The Armenians stayed close to the original Indo-European homeland, where they are today. The Phyrgian tribe probably followed the Greeks into Anatolia. The remainder of the Indo-European community then moved north, onto the steppe plains of central Asia. From here they would conquer Europe.
The evidence for this movement comes from the Indo-European dialects from which European languages are descended. There are loan words in the ancient European languages from the Finno-Ugric language family (which includes modern Finnish and Hungarian) and words that are clearly borrowed from the Altaic (Turkish) language family. Contact with these families of central Asia give testimony to the sojourn of the Indo-Europeans there.
Circling back to the west, the ancient Europeans settled for a time north of the Black Sea in a loosely federated community. We can think of this region, the plains of the Ukraine, as a second homeland for the remnant of the original Indo-European tribe. From around 2000 B.C. through the first millennium B.C., speakers of ancient European languages spread gradually into Europe. Their coming is demonstrated archaeologically by the arrival of the "pit grave" culture, which buried its dead in shafts, or mounds.
It seems the tribes that settled the Balkans went first -- the Thracians, the Albanians and the Illyrians. Then the Celtic and the Italian tribes set out, the Celts going north of the Alps into western Europe, and the Italians south of the Alps into the Italian peninsula.
After a few centuries, the German tribe began its migration, which would continue for centuries, during the Roman Empire, after its fall, and into early medieval times.
Lastly came the Slavic tribe, which after 600 A.D. split into three groups. One went south into the Balkans, one went west (and into continuous conflict with the Germans), and one stayed where they were in southern Russia. Meanwhile the Baltic tribe at some point had moved to the shores of the Baltic Sea.
The Indo-European Diaspora was complete. In the 1500 and 1600s A.D. a second Diaspora would occur, this time by ship, and Indo-European languages would encompass the globe and reach every continent.
When a people with a unique culture and language move in and conquer an area that already has an indiginous people with their own language and culture, one of three scenarios can occur:
1. The new people will rule the native people, but will inter-marry with them, gradually adopt the indigenous forms of governance, culture, art, and language, and eventually be absorbed. This happened when the Mongols conquered China. In a few generations, the Mongols were transformed from fierce horse-riding nomads speaking an Altaic language into a self-indulgent, silk-swathed ruling class speaking Chinese -- just another in a long-line of Chinese dynasties. Or . . .
2. The new conquerors and the indiginous peoples can live uneasily together, side-by-side, separate and unequal, until over time the two cultures gradually merge into a third culture bearing elements of the original two. This happened when the Norman French conquered Saxon England, utimately resulting in an English language and culture with both Germanic and Latin/French components. Or . . .
3. Most rare, the conquering people can obliterate the indigenous people entirely, with only the place-names of rivers or districts left to let anyone know that the native people ever existed at all. This is essentially genocide. This happened in the eastern United States, where people today speak English, have an English-based culture, and all the cities and towns have English names -- but the rivers and mountains (and casinos!) have Algonquian, Athabaskan or Iroquois names.
The unusual thing about the Indo-European Diaspora is that in virtually ever case, scenario #3 occured. It is possible that some Indo-European tribes moved into Mesopotamia (the Hurrians and the Kassites were possibly Indo-European until absorbed by the Babylonians and Assyrians). But for the most part, wherever they settled, the Indo-Europeans overcame the existing population and imposed totally their language, their culture and technology. In all of western Europe (for instance) the only remnants of the original Europeans are the Basque people clinging tenaciously to the Pyrenees Mountains . . . numerous megalithic stone monuments . . . and some river names in France and Belgium.
Why?
Perhaps the Indo-Europeans with their advanced agriculture were too numerous to be stopped. Perhaps the centuries of close contact with livestock had infected them with diseases for which they (but not their enemies) had grown immune. Perhaps their mastery of the horse and chariot allowed total military supremacy. Perhaps the Indo-European language itself, which is highly inflected (new words and concepts can be built up from existing pieces of words and concepts) was an suberbly powerful tool for promoting human culture.
Perhaps some or all of these . . .