The Indo-Europeans went through the area on their way to else where.
Some rather large migrations came from the east and went to the west, Mongols and Huns to name just two. Both took slaves by the many many and sent them back to their homeland to for work, play and breeding stock.
Oh, and before there were Russians, there was the Rus warlords stomping through the area doing the same thing as the Hun and Mongols.
That there’s a lot of genetic mix is kind of a - duh, I would think.
Oh, and Eurasian women can be incredibly hot.
At some point in prehistory, the Indo-Europeans came from there. During the natural pulse of the climate, there have been large-scale egresses from Central Asia, spilling out in all directions, including into India, Mongolia, China, the steppe and Europe, Anatolia, and the Middle East.