When he became emperor he set out to complete the occupation of the whole subcontinent, and attacked the independent state of Kalinga-modern-day Orissa on the east coast.
The Gupta Dynasty began a little after the year 300, and it rapidly expanded from its base in northern India, until it covered a good deal of the subcontinent.
The Amazon rainforest is enormous, larger than the entire Indian subcontinent but with a population under 20 million, meaning that several cities across the world have more people than that.