Nationality

It might be defined by a set of cultural mutations; anything else is an accident, except for one’s sense of identity. Like religion, chances are it’s an accident of one’s birth. Residency and a legal procedure can change one’s nationality, but not one’s language or religion or even one’s sense of identity. A person whose first language is Arabic but also speaks English and who grew up in London— its schools, BBC, the Daily Mail— could be English, but if the same experiences were elsewhere, no? There are more differences between individuals than between nationalities.