So i am guessing you have trouble differentiating these 3 very different things?
* Race. Examples caucasian/white, asian, black. Hispanic.
*cultures. Arab, Slavic, Mediterranean, Nordic
* nationalities. English, German, Ukrainian, Russian, American, etc etc etc
These are 3 very different things which you are conflating.
* and nearly all people in the area of conflict and region surrounding descended from the same nation-state ( Keivan Rus) and are genetically intermixed as well as having common ancestors. This is the case pretty much all over the world...only where there have been instances of mass migration or where a nation is conquered and then settled by folks who are genetically very different from them AND their very similar neighbors does this usually differ.
Good example:
Before Europeans colonized the US and eventually conquered and settled it....the indigenous peoples...Native Americans...are very similar to both the indigenous peoples of Mexico to the south, and Canada to the North. They are all brown skinned, dark haired folks with similar peoples that intermixed. It was only when this country was conquered by England, became the US, and welcomed immigrants from all over the world...then had a couple hundred years to reproduce...that we have a US population which is very different from our neighbors. Makes sense, right?
Edit: had to delete last paragraph bc reasons