Complex sentence: By the beginning of the 20th century, Islam and Hinduism had coexisted in India for over a thousand years, and barring the occasional outbursts of violence, the two religious communities had lived together peacefully and shared strong social bonds except marriage.
Split into simpler sentences: By the beginning of the 20th century, Islam and Hinduism had coexisted in India for over a thousand years. Barring the occasional outbursts of violence, the two religious communities had lived together peacefully and shared strong social bonds except marriage.