The predominant religion in ancient India was Hinduism. The roots of Hindu religion can be traced back to the Vedic period. Hinduism is believed to be the oldest of major religions and originated in northern India. Early Aryan, or Vedic, culture was the early Hinduism whose interaction with non-Aryan cultures resulted in what we call Classical Hinduism. It is interesting to note that much of ancient, classical and modern Indian culture has been greatly shaped by Hindu thought.
The Mahabharata and Ramayana, both sacred Hindu texts, served as India's main motivating base for a great deal of literary, artistic and musical creations in subsequent millennia. The Epic Period was a golden era in Indian philosophical thought because of the tolerance of different opinions and teachings. The most popular form of Indian medicine, Ayurveda, was developed by Vedic saints and Jyotish, Hindu astrology, is the most popular form of astrology in India today. Yoga, an internationally-famous system of meditation, is one of six systems of Hindu thought.
Besides Hinduism, other main religions during ancient India were Buddhism, and Jainism. Buddhism 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. 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.
There also developed many heterodox religious sects in ancient India. One such sect was Ajivika, founded by Mahavira's rival Goshala Maskariputra. Ajivikas did not believe in karma and thought that the destiny was predetermined and could not be changed. There were also several other religious contemporaries to Buddha and Mahavira during the 6th century B.C. Another preacher of the same period was Pakuda Katyayana, who also taught that the soul was superior to good and evil, thus unchanged or untouched by it. He classified everything into seven categories, i.e. earth, water, fire, air, pleasure, pain and soul, which were eternal. Ajita Kesakambalin, another contemporary of Buddha taught complete materialism. He did not believe in the afterlife and considered death as the final phase of all souls.