Buddhism is an eastern religion that according to Buddhist teachings was founded by Siddartha Gautama, an Indian prince who became disenchanted with his life and decided to seek enlightenment. He studied under the famous religious teachers of the day, mastered the art of meditation and tried to end his inner suffering. When established techniques didn’t work, he developed his own set of principals, which became the core teachings of Buddhism, known as the Four Noble Truths and the Eightfold Path. According the Therevada, he was able to reach enlightenment and end his suffering before dying at the age of 80.
Buddhists believe that since life is suffering, the only way to end suffering is to remove yourself from it so as to remove yourself from wants and desires. The way to do this is the Eightfold Path developed by Siddatha. Buddhists also believe that the universe is cyclical, and therefore the way one acts is the type of treatment one received. This is called Karma. Buddhists also believe in reincarnation, where ones good deeds or bad choices affect how one is reborn in their next life. If someone is bad, they are reborn as a lesser spirit. If one is good, they are reborn as a higher being.
Buddhism spread through the travels of practitioners, along the Silk Road and thanks to the conquests of Emperor Ashoka. Ashoka helped create a more formal relationship between Buddhism and the state by ruling with the approval of Buddhist leaders. He helped support monks and establish centers of Buddhist learning throughout India during his reign.