Ancestral lands
Genetics tell you where you're from and, if your descendants stayed in one area long enough, your ancestral land.
My genetics cover mostly one area of the European continent.
The rest is modern history.
Intermixing shows the recent locations my part of Europe decided to move to in the last 500 years.
It is interesting to note that, although lots of wars were fought and lots of movement occurred between countries, people mostly kept to themselves and their people. Of course, invasions occurred, intermixing occurred in small layers over time and travel was commonplace for nobility.
The reason that we have such distinct ancestral heritage in the first place is because of closed populations. If you're 100% basque, you can proudly say that your people never left the Basque region and never intermixed. Kinda cool to belong to one area.
If constant intermixing happened just like we see portrayed in historical period pieces and movies, many of us would probably be unable to pinpoint exactly where we are from.
-Updated and uploaded again with grammatical fixes