Smaller regional centers across the north, under Kushan control in the early centuries of the first millennium A.D., are brought together under the Gupta dynasty in the fourth century. Mahayana Buddhism flourish; the earliest paintings preserved in India (fifth-century cave paintings) depict the Buddha and scenes from his life. Buddhism spreads to Central Asia and China along international trade routes. The religion known as Hinduism assumes ritual and artistic form, and Hindu sculptures and temples proliferate. India trades with Rome and other cultures to the west, including Southeast Asia.
Buddhism spreads to Central Asia and China via the Silk Road, a transcontinental trade route connecting the Mediterranean world to China through Central Asia. South Indian kingdoms also engage in extensive trading contact with Rome, cultures to the west, and parts of Southeast Asia.
Hindu sculptures and temples proliferate in this period, as seen in the rock-cut shrine at Udayagiri (near Bhopal in Central India), built in the reign of Chandragupta II at the end of the fourth century. Early freestanding temples are built of brick and house the image of the deity in what is called the garbha-griha (womb chamber). One of the earliest stone Hindu temples, dedicated to the god Vishnu, is built at Deogarh in Central India, reflecting Pancharatra ("five rights") beliefs that Vishnu takes on different forms as creator, preserver, and destroyer. The temple platform, which now exists only in fragments, features scenes from the stories of Rama and Krishna. As symbols of political power and authority, images and temples are built and maintained by rulers to assert independence and sovereignty. In some cases, the appropriation of an image associated with a competing or prior dynasty acts as a means of establishing supremacy over or continuity with such a dynasty.