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When Alexander returned from India, he left a power vacuum into which stepped Chandragupta, the first emperor of the Indian Mauryan Empire. Chandragupta became the undisputed ruler of northern India and, for the first time in Indian history, gave the area a degree of political unity.
After ruling for some 25 years, Chandragupta Maurya, according to various sources, became a monk and starved himself to death. His son, Bindusara, extended his empire, but it was Bindusara’s son Ashoka who, after waging a brutal war of expansion against his enemies, gained remarkable fame in India through his conversion to Buddhism – a way of life that had gained many adherents since its introduction in the 6th century BC. Shocked by the aftermath of a major battle, Ashoka renounced all violence and preached Buddhism and peace throughout his kingdom and abroad. Upon his death in 232 BC his family managed to hold on to power for another half a century or so before the last Mauryan emperor was murdered and India became divided once again. Periodically invaded, northern India would only become prosperous and stable again under the Gupta Empire in the 4th century AD.