Saylor.org's Ancient Civilizations of the World/The Mauryan Age
The Rise of the Mauryans 
The expansion of two kingdoms in the northeast reagion of the Indian subcontinent precipitated the emergence of India's first empire, ruled by the Mauryan dynasty (321-185 BCE). By 303 CE, Chandragupta Maurya had gained control of a vast swath of the Indian subcontinent running from Bengal in the east to Afghanistan in the west, and pushing south about halfway down the peninsula. The success of Chandragupta Maurya is accredited to his prime minister and mentor, the shrewd tactician Kautilya. Chandragupta's son, Bindusara, would further extend the empire in the south and the central regions of India, but it would be the next emperor who would truly be remembered as extraordinary.
The Emperor Ashoka 
The Emperor Ashoka (r. 273-232 CE) is one of the most famous rulers in Indian history. His conversion to Buddhism gave the religion a seal of legitimacy much in the same way the conversion of the Roman Emperor Constantine to Christianity would do the same for that faith. He began by ordering that his edicts be carved into stones and caves around the empire. Years later, he began ordering that his edicts be carved into large sandstone pillars topped with statues of lions. He also was responsible for the erection of over eighty thousand buddhist stupas to house the relics of Buddhism.