Question
What caste are foreigners?
Answer
How is caste determined? What we call as caste in english is called varṇa in sanskrit. One of the meanings of varṇa is color, specifically of the mind, i.e character or nature. Though birth can play a significant role in shaping up one's nature, from the point of view of Bhagavad Gita and Srimad Bhagavatam, birth does not draw a hard line on what caste a person belongs to. In fact the emphasis is clearly on guṇa (nature) and karma (activities).
Bhagavad Gita 4.13 says
According to the three modes of material nature and the work associated with them, the four divisions of human society are created by Me. And although I am the creator of this system, you should know that I am yet the nondoer, being unchangeable.
And in chapter 18 of the Gita the nature/activities of the varnas are further described as below:
Bg 18.41 — Brahmanas, ksatriyas, vaisyas and sudras are distinguished by the qualities born of their own natures in accordance with the material modes, O chastiser of the enemy.
Bg 18.42 — Peacefulness, self-control, austerity, purity, tolerance, honesty, knowledge, wisdom and religiousness – these are the natural qualities by which the brahmanas work.
Bg 18.43 — Heroism, power, determination, resourcefulness, courage in battle, generosity and leadership are the natural qualities of work for the ksatriyas.
Similarly in Srimad Bhagavatam also this topic is discussed by Sri Narada Muni in canto 7 chapter 11 . There his conclusion is:
SB 7.11.35 — If one shows the symptoms of being a brahmana, ksatriya, vaisya or sudra, as described above, even if he has appeared in a different class, he should be accepted according to those symptoms of classification.
Finally I would like to mention that regardless of what varṇa one may belong to, it is not a hindrance for attaining the Supreme Lord. This fact is mentioned by Lord Krishna in the Bhagavad Gita:
Bg 9.32 — O son of Prtha, those who take shelter in Me, though they be of lower birth – women, vaisyas [merchants] and sudras [workers] – can attain the supreme destination.
What caste do foreigners belong to?
General Perspective: Since these people do not follow the varna system of Vedic culture the terms like mleccha and yauvana are used to describe them. These terms indicate they are less than sudras. You can find these in sanskrit dictionaries like Monier or Apte. A description of these races can be found in the purport of Srila Prabhupada to Srimad Bhagavatam 2.4.18 where he connects the places outside modern India to the original Bharata Varsa using references from Mahabharata.
However when any of the foreigners take up the Vedic culture their classification wouldn't be any different than the Indian Hindus according to the Gita and Bhagavatam references above. Having a birth in different land or religion is not a barrier. This practice is prevalant in Gaudiya Vaishnava tradition where many brahmanas and sanyasins are from foriegn origin.
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