Be it for race, nationality or language (vs dialect), there are always several levels (imagine a "zoom in/out" option
). We could consider the EU as a nationality, but it could also be at the level of member-state (e.g. France, Spain, UK, Belgium...) or at a smaller regional level (e.g. Corsica, Catalonia, Scotland, Flanders...). All are valid categories of nationality, depending on one's feelings.
Likewise, one could consider French, Spanish and Italian as languages and Catalan, Galician, Occitan as dialects. But we could also consider them all as languages, or all as dialects or Latin...
It is the same for racial/ethinc groups. We could see big divisions such as Caucasian, Mongoloid, Negroid... or smaller ones like Germanic, Celtic, Latin, Slavic... or even smaller ones like Scottish Celtic, Irish, Celtic, Cornish Celtic, Iberian Celtic, Anglo-Saxon, Frankish, Scandinavic, Gothic...
But in any case, it is not possible to mix Black peolpe with Anglo-Saxons, or Latins with Japanese, or Indian with Jewish... I also don't think that the Arabic race should include the mainly Euro-African Berber, because the proportion of Arabic blood is just too tiny, even if they are linguistico-culturally Arabic.