Ashoka's turn after the Kalinga war
Around 261 BCE the Mauryan emperor Ashoka conquered Kalinga (in present-day Odisha) in a war that his own inscriptions say killed or displaced well over a hundred thousand people. Afterwards he declared remorse, gave up conquest by the sword, and promoted dhamma: tolerance, non-violence, and care for subjects and animals. He had these principles carved on rocks and pillars across the empire in local languages and scripts, so that the ruler's moral message would reach ordinary people directly.