5000 years ago, nomadic steppe lifestyles began with the Yamnaya people, likely speakers of Proto-Indo-European, who left kurgan graves across the steppe, and whose descendants spread across half the world.

Check out the REHP blog for a map of the Yamnaya homeland https://therussianempirehistorypodcast.com/blog/episode-103-early-kurgans-and-the-yamnaya-culture