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 261 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 . According to the rock edict 13 , both sides suffered losses,but people of kalinga suffered the most .
Although he won the war, Asoka 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 inscription for wanting that his son and grandson also never 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 propogate dhamma.