I'm very interested in finding my ethnic origins. Culturally, I'm as South Indian as it gets. South Indians are the descendants of the original Indians [Indus Valley, anyone?] or Dravidians. However, my language is a very weird and ancient mixture of Sanksrit and Dravidian influences. I speak the "purer" Sanksrit version of the language, ostensibly since I'm a Brahmin.
As entanglement mentioned, inter-marriage never happened back in the day, so I can safely assume that my ancestors were Indo-Aryans. Brahmins are of course, the evil priestly class who were [and still fucking are] all about keeping the "purity" of our Vedic past. The rituals that we participate are said to have originated in 1400 B.C., so I'm pretty fucking confused.
The vast majority of South Indians are quite dark-skinned, but most of the Brahmins are quite fair-skinned. I'm scarily fair-skinned for a South Indian and have light brown eyes. More often than not, in America, I've been asked if I was Iranian/Turk/Arab/Latino before I tell them that I'm Indian.
After living in America and seeing so many different ethnicities, I'm now very interested in identifying my roots. Since the British took over, the South Indian naming standard evolved into this formula - First name-Place of Origin, Middle name-Dad's name, Last name-"First" name. Therefore my last name only traces to the village in which my Great-grandfather grew up in.