Quote from HoundDogOne:
East European history is subject to great debate...
Primarily because the Soviet Union spent 3 generations methodically rewriting East European history.
Here's an article called "Period of Mongol Invasion and Rule, 1237-1480"...
So that is 243 years.
http://russia.nypl.org/history/mongol.html
Assumming "Mongol Rule"... the genetics flows automatically.
Obviously... the Mongols would chose to have sex with upper/ruling classes...
And with the most beautiful and intelligent of the peasant class.
As an East European...
If you go to any EE major city...
You will very, very commonly see Mongol features among the people...
While if you go to the villages...
You will see a predominance of Euro-Slavic features.
The Russian ruling class probably absorbed more Mongol genetics then any other Slavic group...
Just look at these guys... Lenin, Stalin, Brehznev, Yelstin... all significant Mongol features.
But even greater...
Was the cultural and institutional impact...
Because the Mongols imposed many of their ways on occupied lands...
And that is why Russian culture and values...
Have more in common with the Mongols than with Europe.
This is all very debatable...
But Westerners would do well to understand that Russians are Euro-Mongols... not plain Euros.