Around 500 B.C Indian King Chandragupta found the Mauryan Empire in northern India which was later streched by his son Bindisara to Persia(present day Iran). After the death of Bindusara, his son Ashoka the great took the responsibility and assured his father the biggest Empire on the planet under Mauryan flag.
Ashoka around 350 B.C became the king of the vast Mauryan Empire and took the oath to win the world. Within 7-10 years of his Kingship the Mauryan Empire stretched from India to Persia(Iran), Mesopotamia(Eastern Europe), southern Tibet and SE Asia (Thailand, Burma). Ashoka defeated every empire originated in South Asia and the Middle East. He formed the vast political Kingdom ever on the Planet.
But just one kingdom was remaining to be defeated i.e. Kalinga (modern state of orissa in India). No other emperor ever invaded the Kingdom due to the fear of a huge innocent massacre. There was no king or queen in the kingdom yet it was called the Kingdom due to such a big govermental inluence of the common people icluding farmers, traders etc.
Ashoka invaded the region around 330 B.C and it is said that approx. 10 million people were killed by the Ashokan millitary to annex the kingdom. After winning the kingdom Ashoka became the most powerful and the cruelest King the world had ever seen. His millitary force consists of more that 20 million soldiers who then used to control the largest empire of the Earth.
In the later years of his life Ashoka regreted killing of innocents to annex the Kalinga and became full of remorse. He then adopted the preachings of the Indian prince Siddhartha Gautama (Buddha) and spread it to his SE Asian empire. In those years there used to be no other known relegion except Ancient Vedicism(Vedic Hinduism) and Gautama Buddha used to preach the depth and medication of the Vedicism. These teachings were later combined to form a new relegion known as Buddhism.
Buddhism in SE Asia (Burma Thailand China HongKong) is due to the efforts of great Indian emperor Ashoka.
Jim - Fool he was the greatest emperor of India.