I am posting this in response to something I just watched called "What It Mean To Be Pro-European?" The person who made it is working under this mistaken belief that European nations are somehow homogeneous.
This Alsatian/German-Belgian/Polish-Ukrainian/British/Balkan/etcetera person calls bullshit.
This animation sucks because is only shows the Northern shore of the Med. European culture has been tied to Asia and Africa since prehistory.
And let's not forget that Europeans have been at each other's throats for millennia, but I can't prove that since that also gets into prehistory. And some groups find themselves living with other groups. And fighting over which alphabet to use, or which religion to follow.
And that's even within Christianity.
Let's not forget that Europe is a stone's throw from Africa in the West (at Gibraltar) and connected to Asia/Middle East in the East. Islam has had an influence on European culture. Especially Spanish culture. After all, Europe is separated from Africa by the Mediterranean.
The Celts, Romans, and Vikings all spread out and went native while we're at it.
Italy and Germany only date to the mid-19th Century. But some European countries are more recent than that. After all, Yugoslavia had a bad break up. They don't call it "Balkanisation" for nothin' (can't forget I have Balkan in me as well).
I call myself "European" since that is the best way to describe myself since my ancestors came from countries which no longer exist, or were swallowed up by other countries. Also, accepting the diversity of cultures, some of which I can't relate to, requires me to take on a blanket term.
And, unless I want to be really provincial in the true sense of the term, I have to describe myself using a blanket term. People from the United States describe themselves in a blanket term as well since they call themselves "Americans" or US citizens, not citizens of the state they are from.
Brexit has shown that "European" isn't a national descriptor, but a blanket term for people living in the European continent: no matter what their ethnicity. Likewise, the same applies to US citizens.