This article does not have any sources. (December 2020)
The Kalinga War was a war fought between the Mauryan Empire and the state of Kalinga. Kalinga was an important kingdom because it controlled the trade routes with Southeast Asia. Because of this, Ashoka, the Mauryan king, wanted to capture it. Therefore, he lead his huge army to Kalinga in 262 BC.
According to Megasthenes, the Greek historian at the court of Chandragupta Maurya, the ruler of Kalinga had a powerful army comprising infantry, cavalry and elephants. After the War, 150,000 thousand men and women were deported from Kalinga and forced to work clearing the wasteland for future settlements, and forbidding them to ever return to their old homeland. The descendants of the Kalinga people migrated later to the sindh. From there they migrated to Persia, Mesopotamia, Egypt and Europe. It is possible that the descendants of these people are the Roma of Europe.
Although he won the war, Ashoka realized the futility of war. He saw the bloodshed and suffering of the soldiers' families. He vowed never to fight again. He converted to Buddhism and he dedicated his later life to help his subjects. He left the conquest after winning a war. He wrote inscriptions for wanting that his son and grandson also never to think about war. He decided to observe Dhamma (a common code of conduct). He was also inspired by the teachings of Buddha. He sent many Buddhist scholars to distant lands in order to propagate Dhamma.