The Gupta rulers gave patronage to Bhagvatism. But they were tolerant to other religions too.
The Chinese pilgrims Fa Hien and Hsuan Tsang, who came to India during the reign of Chandragupta II and Harsha respectively, clearly give the impression that Buddhism was also flourishing.
Harsha, though a Shaiva in his early life, became a follower of Buddhism and a great patron of the religion.
He convened an assembly at Kanauj to publicize Mahayanaism.
Nalanda developed as a great center of education for Mahayana Buddhism during his time. Students from outside countries also came to study in this university.
According to Hsuan Tsang the revenues of one hundred villages supported it.
Bhagvatism centered on the worship of Vishnu and his incarnations.
It put emphasis on bhakti (loving devotion) and ahimsa (non killing of animals) rather than Vedic rituals and sacrifices.
The new religion was quite liberal, and assimilated the lower classes in its fold.
In south India, from the seventh century onwards the Tamil saints called Alvars and Nayannaras popularized the concept of bhakti.
Alvar saints popularized the worship of Vishnu and the Nayannar saints, the worship of Shiva.
Spread of Tantrism in India in this period.
From the fifth century the brahmanas had started receiving land in the tribal areas of Nepal, Assam, Bengal, Orissa, central India and Deccan.
As a consequence, the tribal elements came to be assimilated in the brahmanical society.
It is this assimilation of brahmanical religion and tribal practices which resulted in the development of Tantrism.
It did not believe in any caste or gender bias and admitted both women and shudras in its ranks.
It put emphasis on ‘female’ as a source of power and energy.
The Tantrik concepts affected, Shaivism and Vaishnavism as well as Buddhism and Jainism.
It resulted in the introduction of the worship of female deities in these religions.