There are only two rulers who are justified as great emperor in the history of Indian Subcontinent, Mauryan Emperor Ashoka the Great and Mughal Emperor Akbar the Great. Ashoka (from 304 BCE to 232 BCE) was the third ruler of the famous Mauryan dynasty, built one of the biggest empires at his time and became a fabulous model of kingship on the Buddhist custom. Buddhism started to prosper and publishinate all over the world during his rule.
As a son of a royal family, Ashoka acquired military training during his childhood and grew up an excellent hunting skill. There is a myth about Ashoka is; he alone killed a lion with only a wooden rod. Although his way of conquering throne was not easy, his step-brothers became his biggest enemy and competitor. Ashoka's father Emperor Bindusara nominated his elder son Susima as his inheritor but due to Susima's arrogance, cruelty, and imprudence he was not supported by the ministers. An influential minister named Radha Gupta played a vital role to establish Ashoka as an emperor, and later he became the chief minister of Ashoka's Government.
In the early stages, Ashoka ruled the empire just like his grandfather founder of Mauryan Empire emperor Chandragupta did, in an efficient manner but brutally. He formed a vicious army and used it to enlarge his empire. To punish the criminals he created a prison called "Ashoka's Hell" where prisoners were tortured in a sadistic way.
In the 8th year of coronation, Ashoka invaded a feudal province named Kalinga, which is famous as "Kalinga war" in the history. The Mauryan army two thousand two hundred years ago was as well organized as any that came before it or after. The chain of command was well forged. Day and night the generals passed to draw a battle plan to deliver to Ashoka for his review. Six soldiers in a circle protected a horseman; five horsemen circle a war elephant. So disciplined was that army that when it charged it charged as one. As an outcome, this war became one of the bloodiest and ruthless war in the history. The people of Kalinga tried their best and offered a tough resistance to save their honor, their motherland. But their strength was far beyond than the Mauryan army. About 100,000 were killed, and 150,000 were imprisoned. The whole Kalinga turned into a graveyard.
After Kalinga war, Ashoka became the master of all what he saw and much beyond. He conquered almost the entire Indian subcontinent except the extreme southern province of India which he could have easily taken, but he did not. The destruction of Kalinga war made a huge impact on his mind and was unable to justify the distinction between victory and defeat. He abandoned his expansion policy and decided to win his people mind, make his empire prosperous and peaceful.
Ashoka soon adopted Buddhism and disseminated the message of kindness, love and peace. Ashoka built thousands of educational institutions, hospitals, roads. He improved water transit and cultivation system as well as trade and agriculture. He made rules to enrich the values of the society. He carved inscriptions describing his legacy and culture on pillars and rocks which are seen until today.
After successfully ruling 40 years, at the age of 72 Ashoka took his last breath. When Ashoka died, no one could take his place with none to lead it. His great empire collapsed under its own weight.