Proto-Indo-European is the ancient ancestor of many of the world's languages, including Russian, Farsi, English, and Greek. However, since it was never written and was spoken around 5000 years ago, scientists are still unsure of who its speakers were and where--and when--they lived.
The speakers of Proto-Indo-European lived on the Pontic Steppe north of the Black Sea.
Pontic Steppe Homeland
According to genetic, archaeological, and linguistic evidence, the Proto-Indo-European homeland was the Pontic Steppe, which ranges from modern-day Ukraine and Moldova to northwestern Kazakhstan.
The speakers of pre-Proto-Indo-European lived in Anatolia, which is in the same area as modern-day Turkey.
A combination of linguistic and archaeological evidence shows that the pre-Proto-Indo-European homeland was in neolithic Anatolia (modern-day Turkey) and that this language subsequently split into different varieties of Proto-Indo-European.
The speakers of Proto-Indo-European lived in northern Mesopotamia, eastern Anatolia (modern-day Turkey), and the southern Caucasus.
Over time, the Proto-Indo-European homeland ranged from eastern Anatolia to the southern Caucasus and Northern Mesopotamia. In present-day terms, this includes Turkey, Armenia, Azerbaijan, Georgia, Syria, and Iraq.