Is Caste system, particularly untouchability as practised by the Hindus, was it sanctioned (e.g. Sharia Law in Islam) by the ancient sacred religious texts or is it imposed by modern Aristocrats to enslave the poor people, similar to Slavery as practised in Western Countries, particularly US?
Caste system/untouchability was not sanctioned in hinduism or the texts. Most of the texts explain about how one has to live both internally and externally to attend moksha. Most of the books are explanatory with stories to understand the life style or culture one should inculcate to have correct way of living. The religious discrimination started with diversified influences in time but the core hindu nature doesn't discriminate among the living begins. "Sarvhe janha sukhinobavanthu" meaning "Let all kinds of people attend the happiness (pure conciousness or divinity)"