Korean shamanism, today known as Muism (Mugyo, "religion of the Mu") or sometimes Sinism (Shingyo, "religion of the gods", with shin being the Korean character derivative of the Hanja), encompasses a variety of indigenous religious beliefs and practices of the Korean people and the Korean sphere. In contemporary South Korea, the most used term is Muism and a shaman is known as a mudang (무당, 巫堂) or Tangol (당골). The role of the mudang, usually a woman, is to act as intermediary between a spirit entity, spirits or gods and human beings.
Women are enlisted by those who want the help of the spirit world. Shamans hold gut, or services, in order to gain good fortune for clients, cure illnesses by exorcising negative or 'bad' spirits that cling to people, or propitiate local or village gods. Such services are also held to guide the spirit of a deceased person to higher realms.
Koreans, like other East Asians, have traditionally been eclectic rather than exclusive in their religious commitments. Their religious outlook has not been conditioned by a single, exclusive faith, and even though many Koreans converted to Buddhism when it was introduced to the country, the influence of Muism was still strong even among Buddhists. This changed during the long period of Korean history during the later colonial period, when Christian missionaries demonised mudang and Muist followers, and since the significant expansion of Christianity in South Korea between the 1960s and the 1990s. However, in 2007 a resurgence of Muism in South Korea was reported, where it is practised by around 8% of the population. In North Korea roughly 16% of the population is Muist.
Korean shamanism is distinguished by seeking to resolve human problems through a meeting of humanity and the spirits. This can be seen clearly in the various types of gut (굿) that are still widely practiced. Korean shamans are similar in many ways to those found in Siberia, Mongolia, and Manchuria. They also resemble the yuta found on the Ryukyu Islands, in Japan. Jeju Island is also a center of Korean Shamanism. Muism has exerted influence on the basis of some of the Korean new religions, such as Cheondoism.
According to various sociological studies the strong similarity and convergence of native Korean shamanic mythos and the Christian core have favoured the spread of Christianity in South Korea, and even shaped the intimate features of the Korean Christian approach.
Read more about Korean Shamanism: Origins, Place in Society, Revival As Cultural Society, Types of mudang, Shinbyeong (spirit Sickness), Rituals or gut (굿), Regional Shaman Rites