[Cronos]

They wiped out Buddahism in India though.

Actually Buddhism wasn't wiped out in India by violence at all -- the people slowly reverted back to Hinduism, or rather a form of Hinduism different to what was practised before Buddhism -- the earlier form was Vedic Hinduism and the latter form Brahminical Hinduism. It's not clearly known why exactly Buddhism peterd out (the Mauryas were rulers over the entire Indian continent and promoted Buddhism, but the Guptas who came much later were Hindu, so I guess the lack of royal patronage caused Buddhism to decay -- though it spread at that time to Central Asia and China and South East Asia.

[econ_grad]

Asoka was the last ruler who supported Buddhism in his later life. Sankaracharya was able to bring a lot of Buddhists back into Hinduism by his vast social reforms.

[FreedomSurge]

Try incessant Muslim raiding on the rich Buddhist temples and the murder of the monks.