The Cathars were a religious group that emerged in the 12th century in southern France. They followed a dualistic belief system, viewing the material world as evil and the spiritual realm as good. This perspective led them to reject the teachings of the Catholic Church, which they believed was corrupt. Catharism emphasized personal spiritual experience and the importance of living a simple, ascetic life. Their followers, known as Perfects, practiced strict moral codes and sought to achieve spiritual purity. The movement was ultimately suppressed by the Albigensian Crusade in the early 13th century, leading to the decline of Cathar beliefs.