The Aryans arrived in India around 1500 BC from Central Asia. With their superior iron weapons and horse-drawn chariots, they were able to conquer the Indus River Valley peoples. The Aryans then introduced their religion of Hinduism to India and established the caste system, which divided society into rigid social classes based on birth. Under the caste system, the Untouchables performed the lowest jobs and were considered beneath all other groups. Hindus also believed that people's souls were reborn after death into different castes as a reward or punishment for their deeds in a past life.