The Maurya Empire (322–185 BCE), ruled by the Mauryan dynasty, was a geographically extensive and powerful political and military empire in ancient India.
Originating from the kingdom of Magadha in the Indo-Gangetic plains (modern Bihar and Bengal) in the eastern side of the sub-continent, the empire had its capital city at Pataliputra (near modern Patna). The Empire was founded in 322 BCE by Chandragupta Maurya, who had overthrown the Nanda Dynasty and began rapidly expanding his power westwards across central and western India taking advantage of the disruptions of local powers in the wake of the withdrawal westward by Alexander the Great's Macedonian and Persian armies. By 316 BCE the empire had fully occupied Northwestern India, defeating and conquering the satraps left by Alexander.

taken from WIKIPEDIA