Ashoka, the great Mauryan Emperor of India use the concept of dhamma to avoid resorting to violence? How?

According to the stories which surround Ashoka, he began his rule in fratricidal bloodshed and violence towards conquered people. Yet within a short period of time, Ashoka changed his policies completely to become a model ruler. By modifying a concept that was well known amongst Hindus, Buddhists and Jains of his time (the concept of dharma, or dhamma), he developed a unique system for governing the largest Indian empire of ancient times. While Ashoka's dhamma policy was avowedly peaceful and paternalistic, it gave India decades of peace in which the country prospered. It was not a vaguely idealistic policy but one which was backed by brilliantly pragmatic statesmanship and public relations.