Looking at the passage in Sutta Nipata, 1.7 (Vasalasutta) it does seem to describe an early form of Hinduism. It is interesting that the Buddha is approaching a Brahmin who is busy with a sacrifice and the Brahmin calls out to the Buddha to stay away: apparently because the shaven monk as a world-renouncer would be able to pollute the sacrifice. After all, the renouncer is as it were sociologically already dead. This would point to an early phase of urbanised and sedentary Hinduism, unless we assume the Sutta Nipata was composed much later and hence reflects an early form of Hinduism which may not have been in existence in the times of Buddha himself. But apart from this, the fact also seems to remain that the Buddha was for all practical purposes a world-renouncer.

Incidentally, in the text of the Sutta Nipata the word for 'outcast' or low caste is vasalaka / vasala allegedly from the Sanskrit vrishala (vRSala).

http://www.tipitaka.org/romn/ This is a link to the Pali Tipitaka.

Yours

Victor van Bijlert