The Roma are much closer to a caste, as far as I know. I mean in terms of their history & behaviour (for want of a better word): the borders of who is & isn't a

The Roma are much closer to a caste, as far as I know. I mean in terms of their history & behaviour (for want of a better word): the borders of who is & isn't a traveller have been more porous over time, while I think the Roma have been about as isolated as any other Indian caste. (But not an expert, and don't have data to hand.)