The answer is Buddhism.
The Gupta Empire was an India empire that existed between the 3rd century CE to 590 CE, they were traditional Hindu, but governers didn't force Hinduism to their population which enabled the spread of other religions, especially the Buddhist religion.
During its prosperous days, many building, sculptures, painting, and art, in general, were made in devotion to Buda and the religion itself, such as the Nalanda, a large Buddhist monastery and center of learning, built in the 5th century, an illustration of the various lives of the Buddha on the walls of the Ajanta Caves in the plains of southern India, and several Buddhist complex.