The Mauryan Empire lead to the spread of Hinduism because it was a major religion at the time and Hindu priests were an important part of the emperor's court. Ashoka, who was a powerful ruler who converted to Buddhism, still had his Hindu priests in his court. He helped the spread of Buddhism as he sent many Buddhist missionaries on trips in hopes of inspiring his people to become Buddhist. He also made a council dedicated to the expansion and reform of Buddhism and many merchants became Buddhist, popularizing it in other locations outside of the Mauryan Empire.
