The Maurya Empire was a geographically extensive Iron Age historical power based in Magadha and founded by Chandragupta Maurya which dominated the Indian subcontinent between 322 and 185 BCE. Comprising the majority of South Asia, the Maurya Empire was centralized by the conquest of the Indo-Gangetic Plain, and its capital city was located at Pataliputra (modern Patna). The empire was the largest political entity that has ever existed in the Indian subcontinent, extending over 5 million square kilometres (1.9 million square miles) at its zenith under Ashoka.

Chandragupta Maurya raised an army, with the assistance of Chanakya (also known as Kauṭilya), and overthrew the Nanda Empire in c. 322 BCE. Chandragupta rapidly expanded his power westwards across central and western India by conquering the satraps left by Alexander the Great, and by 317 BCE the empire had fully occupied northwestern India. The Mauryan Empire then defeated Seleucus I, a diadochus and founder of the Seleucid Empire during the Seleucid–Mauryan war, thus acquiring territory west of the Indus River.