It seems that your ignoring something that lies deeper than nationality, culture.

People in new countries carry their cultural heritage with them. North Americans are steeped in the history and stories of Western Europe.

Tolkien seemed to get sidetracked by the single detail of language, modern English, while talking about the cultural heritage of England from Celts, Germanic peoples, etc.

There's no one or group who justs comes into existence with no past and no connections to something before.