Buddhism

 Buddhism, known in ancient India as Buddha Dharma, originated in northern India in what is today the state of Bihar. It rapidly gained adherents during the Buddha's lifetime. Up to the 9th century, Indian followers numbered in the hundreds of millions. While the exact cause of the decline of Buddhism in India is disputed, it is known that the mingling of Hindu and Buddhist societies in India and the rise of Hindu Vedanta movements began to compete against Buddhism. Many believe that Hinduism's adaptation to Buddhism resulted in Buddhism's rapid decline. Also, Muslim invaders are recorded to have caused massive devastation on monasteries, libraries, and statuary, as they did on Hindu religious life. Many Indian Buddhist populations remained intact in or migrated to places like Sri Lanka, Tibet, and other Asian countries.

Recently, a revival of Buddhism in India as made significant progress. In 1956, B. R. Ambedkar, a freedom fighter during the Indian struggle for independence from the British, and hundreds of thousands of his followers converted to Buddhism in protest against the caste system. Subsequent mass conversions on a lesser scale have occurred since then. Three-quarters of these "neo-Buddhists" live in Maharashtra. Alongside these converts are the Vajrayana Buddhists of Ladakh, Sikkim, and Arunachal Pradesh, a small number of tribal peoples in the region of Bengal, and Tibetan refugees.