From what little I understand of Indian systems the sub-castes are basically just extended family networks and allied families. The entire population of Scotland is less than 6 million, yet according to Wikipedia there are 16 named Scottish clans that begin with the letter A.
> From what little I understand of Indian systems the sub-castes are basically just extended family networks and allied families.
This isn't really true. Castes and sub-castes are endogamous. But the groups are large enough that members wouldn't really have any discernable familial ties with majority of the group.
It's the same with Scottish clans and allied clans. The oldest clans date back over a thousand years and sprouted off-shoots that would be 20 or 30 generations removed when counted back solely from the paternal (named) line (though sometimes the name passes through the maternal line, but this remove still holds). And while less endogamous than Indian castes, historically marriages between antagonist clans would likely be less frequent than between allied clans.
Sometimes clans have expanded themselves by basically recruiting distant relatives who have a different surname. Offering them food or money to change their surname to the clan name.
