I am not arguing whether the practices were right or wrong. Just sharing what I read long back...
Untouchability is practiced across the world in different forms. In the west the discrimination against blacks is almost the same as in India towards Harijans (I prefer this word coined by our Mahatma). But the point to be noted is, if a black comes in contact with the white or vice versa,the punishment (extremely severe) is given to the black.
Where as in India, the punishment is for the brahmins, who has to take bath rather than punishing the other people. Hell lot of difference in the perspective.
But on the other hand, I do accept that the so called upper caste people in India (please note upper caste is not just brahmins) did treat the harijans very badly. I dont think there is a record of a brahmin treating a so called lower class badly, atleast physically. But I do remember reading Prabanchans 'Vanam Vasappadum' that the upper caste hindus (not brahmins) used to even skin people alive for even small mistakes, which is really brutal.