Pataliputra (now Patna) is located at the confluence of the Ganges and Son Rivers in northeastern India. It was the capital city of the Mauryan Empire c. 326–184 b.c.e., when it was perhaps the largest city in the world, and again of the Gupta Empire, 320–550 c.e.

Alexander the Great invaded northwestern India in 326 b.c.e. The invasion had a catalytic effect in inspiring an Indian prince, Chandragupta Maurya, to form the first empire on the subcontinent.

Chandragupta might have met Alexander and, taking advantage of the latter’s death, drove the Greek forces out of India, subdued the tribes and states in northern India, and proclaimed himself ruler at Pataliputra, the capital of a previous local state.

Chandragupta fought and then made peace with Seleucus Nicator, Alexander’s successor in Asia and founder of the Seleucid Empire, who sent an ambassador named Megasthenes to Pataliputra.

Megasthenes kept a diary of his stay in India. The original account has not survived, but segments that were quoted in other ancient works give us the only firsthand information of Pataliputra.

According to Megasthenes, a wooden wall nine miles long and a mile and a half wide surrounded Pataliputra, with 470 towers and a moat that was 900 feet wide. (Modern archaeologists have excavated some huge timbers that date to the Mauryan era.) Six five-men boards in charge of industries, trade and commerce, tax collection, foreigners, vital statistics, and public works administered the city.

Megasthenes also described Chandragupta’s lavish palaces, also built of wood. Nothing remains of the palace except fragments of highly polished columns. Between 250 and 240 b.c.e., Chandragupta’s grandson Emperor Ashoka (who had converted to Buddhism) convened the Third Buddhist Council at this city.

The council dealt with growing dissension within Buddhism over interpretation of Gautama Buddha’s teachings and concluded with expelling the followers of the Great Vehicle, or Mahayana Buddhism, and the completion of the Tripitaka, or Buddhist canons.

Pataliputra declined after the fall of the Mauryan Empire until the early fourth century c.e., when a man named Chandragupta (not related to the founder of the Mauryan Empire) unified northern India and crowned himself Great King of Kings. He also made Pataliputra the capital of his dynasty (320–c. 550 c.e.).

Another foreigner, a Chinese Buddhist pilgrim named Fa Xian (Fahsien) who traveled widely in India between 405 and 411 c.e., provided an account of the city under the Guptas. He described a great, opulent, and largely crime-free city. Religion flourished, with Buddhist temples and priests coexisting with Hinduism.

He also recounted the hospitals in the capital city where the poor received free treatment. Another Chinese Buddhist pilgrim Xuan Zang (Hsuantsang) traveled to India during the early seventh century, studying, lecturing, and visiting Buddhist sites and writing extensively about his travels.

He visited Pataliputra but recorded that little remained of that once glorious city. Earthquakes in the region, the hot climate, and the wooden construction of the structures have left little for archaeologists to retrieve from a once great city.