Simply, Ashoka gave up war for love and peace. After the Kalinga war, he considered himself the reason for the bloodshed and suffering of people. So, he vowed to never take a war.
Who was Ashoka?
Ashoka, also known as Ashoka the Great was an Emperor of the Maurya Dynasty who ruled almost all of the Indian subcontinent from 268 to 232 BCE. He was the grandson of Chandragupta Maurya, founder of the Maurya Empire. Bindusara was Ashoka’s father.
During his reign, he fought a war against the state of Kalinga, an independent feudal kingdom located on the east coast, in the present-day state of Odisha and north parts of Andhra Pradesh. . They faced fierce resistance from the Kalingans. Yet, the Maurya Empire claimed victory and annexed the state of Kalinga.
Beloved-of-the-Gods, King Priyadarsi, conquered the Kalingas eight years after his coronation. One hundred and fifty thousand were deported, one hundred thousand were killed and many more died (from other causes). After the Kalingas had been conquered, Beloved-of-the-Gods came to feel a strong inclination towards the Dharma, a love for the Dharma and for instruction in Dharma. Now Beloved-of-the-Gods feels deep remorse for having conquered the Kalingas.Ashoka, Rock Edict No. 13
Bloodshed in Kalinga War
The sight of such carnage and massacre of human lives and the sufferings of the wounded made a deep impression on Ashoka’s mind. The unhappiness of women and children made him sorrowful.
Ashoka had seen the bloodshed and felt that he was the cause of the destruction. The whole area of Kalinga was plundered and destroyed.
Ashoka vowed never to make war again in his life. He decided to devote the rest of his life to ahimsa (non-violence) and dharma-Vijaya(victory through dharma). Thus the Kalinga war became a turning point in his life.
Following the conquest of Kalinga, Ashoka ended the military expansion of the empire and began an era of more than 40 years of relative peace, harmony, and prosperity.
Kalinga War as the reason for the decline of the Maurya Empire
The Kalinga war led to the decline of the Mauryan Empire. Due to the policy of non-violence, his soldiers fell behind in the art of war. As a result, his gradual decline began. And within 50 years of the death of Ashoka, the Maurya dynasty has fallen.