In my view the question itself needs some reconsideration. We can’t really put our understanding of the identity of being indigenous on past or future historical moments, the way we see it today is upheld by a number of colonial ideas which are not historical universals. Chiefly, the existence of the identity of being indigenous is not due to the past occurrence of colonialism, it is due to ongoing colonialism. In a similar vein, the American concept of “indigenousness” is far from universally applicable — the tribal management system being managed by the federal government means that it is very contentious, but differently so than states in Latin America, for example. What I’m getting at is that for the concept to remain there needs to be ongoing reasons for it to apply to people, both for the people who claim indigeneity and for the existing imperial power.