In just 10 years of paleogenetic research Europeans recovered the genetic history of their continent. Off course this became possible because of decennies of intense archaeologic studies.
The last paper from Posth et al. 2023 about Paleolithic Europe give answers to numerous questions. Let's hope we will have a similar paper about West Asia also.
The first settlers of Europe had the Y dna C1. Then haplogroup I appears with Gravettian culture 35.000 years ago. Given that hg I has common origin with haplogroup J it's quite possible that it entered Europe via Caucasus although a migration via Anatolia is also possible.
Before the LGM the hg I was not popular but things change after LGM. 20.000 ybp a new culture forms in Europe known as Epigravettian and it has strong association with WHG and I2. So the homeland of WHG and I2 is the Balkans. WHG stands for Western European Hunter Gatherers. While in East Europe a different group formed known as EHG associated with R1.
EHG and associated with it subjects like ANE, CHG and Iran and Armenian Neolithic deserves a special thread.
Here I will continue about the WHG which became the predominant population in all Europe before the arrival of farmers.
8500 years ago farmers (mostly G2) enters Europe from Anatolia and local European WHG populations decline substantially. But some time after there is a strong resurgence of I2 and a moderate increase of WHG which never increase over 20-30% in Europe. Today highest affinity to WHG is found in Northest Europe. WHG had an unusual phenotype. Rather dark skin and blue eyes while EHG had more light skin and dark eyes.
Modern Armenians don't have WHG. But do have Y dna I2 (3-3.5%). The I2a2b branch, old name is I2c2. The oldest cases of I2a2b are found in Europe. We now know that this branch came to Armenia 4500 years ago with Steppe pastoralist groups from North of Caucasus who also introduced R1b-Z2103. It was a probably a minor lineage in those groups but expanded a lot with Trialeti Vanadzor culture. Practically all modern cases of I2a2b are from Trialeti Vanadzor Culture. Even if they live in Europe.
We don't know what languages were speaking the WHG foragers in Paleolithic. Some believe that Basque is a WHG language. Some think that nobody speaks their language. In any case Neolithic Europe almost certainly had languages of Anatolian origin. And Etruscan (Tyrsenian family) is a good candidate of being an Anatolian farmers language.
Whatever languages they were speaking the current distribution of I2 and I1 in the world reflects mostly Indo European migrations and massive founder effects. The current young I2a1 branch in Balkans is related to Slavic people. The I1 and some I2 are related to proto Germanic people while the I2a2b in West Asia is an Armenic lineage. (Map 2)