J, David Niven's father and grandfather were Scots born in Perthshire and, though he himself was actually born in London, he often claimed - for reasons best known to himself - to have been born in Kirriemuir, also in Scotland.
Wikipedia describes him as an 'English' actor, so doesn't a person's paternal parentage count any longer as far as his nationality is concerned? If the wife of an American oilman working in Saudi Arabia gives birth to a child there, is that offspring a Saudi? He/she may, of course, be granted dual nationality by Saudi, but surely remains basically American.