Following the invasion of India by Alexander, a military leader of the Nanda Empire, Chandragupta Maurya (321 - 293 BCE), successfully revolted against the ruling powers in India. The Nanda dynasty had conquered most of Northern India and had enacted severe taxation policies. It is possible that Chandragupta fought and met with Alexander. It is certain that in 305 Chandragupta defeated a Seleukid army to take control of the Indus Valley.
Chandragupta abdicated in 293 BCE in favor of his son Bindusura (293 - 268 BCE) and became a Jain Monk. Bindasura Expanded the empire southward .Bindusura was succeded by his son Asoka who is considered one of the most remarkable rulers in history. Asoka added the coastal province of Kalinga to the empire, but after this bloody conquest he is said to have converted to Buddhism and initiated a rule of Moral authority across his empire. His envoys were sent to assure neighbors of his good will and he rewrote a severe penal code enacted by his grandfather. Interestingly, The Greek Baktrian ruler, Menander experienced a similar conversion 100 years later.
Following the death of Asoka the Mauryan Empire began to break apart and the last Mauryan ruler was deposed in 185 BCE. The Mauryan Empire was the largest area under one rule on the Indian subcontinent until the Mughal Empire of the 17th century.