The Presbyterian Church of Korea (PCK; ), also known by the abbreviation "Yejang" (), is a Calvinist Protestant denomination based in South Korea that adheres to the Westminster Confession of Faith.
Korean Presbyterianism originated in the early 1880s with the establishment of the Sorae Church by Seo Sang-ryun in 1884, following his conversion by Scottish Presbyterian missionaries.
As the Presbyterian Mission expanded, the need grew for Korean pastors to serve congregations and provide theological education. In 1907, Presbyterians from the United States, Australia, and Canada established the first theological seminary in Korea, located in Pyongyang. In the same year, the Presbyterian Church of Korea organized its first presbytery and established a governing council.
Since the 1950s, the Presbyterian Church of Korea has experienced a series of schisms, resulting in multiple separate denominations such as the Presbyterian Church of Korea (TongHap) and the Presbyterian Church in Korea (HapDong), primarily over differences in ecclesiology and relations with ecumenical bodies. As of 2019, there were 286 branches in South Korea, with approximately four million church attendees. Numerous denominations that emerged from these schisms continue to incorporate "Presbyterian Church of Korea" in their official names.
Calvinism first arrived in Korea in August of 1866, when pastor Robert Jermain Thomas was captured and martyred during the General Sherman incident. The first Korean Presbyterian church was founded by Seo Sang-ryun in Hwanghae Province in 1884.
Large-scale missions began two decades later, when Horace Newton Allen of the Northern Presbyterian Church entered the royal court of Joseon as a physician. In 1885, Horace Underwood and John W. Heron arrived to establish a formal Presbyterian mission in Korea. Although the first Korean Bible was translated by John Ross in the 1870s, it was later printed by the British and Foreign Bible Society and the Scottish Bible Society in 1886.
Soon after, Canadian missionary James Scarth Gale and Australian Joseph Henry Davies came in 1889, followed by American Samuel Austin Moffett in 1890. In 1891, teachers Isabella Menzies, Jean Perry, and Mary Fawcett arrived from Australia. Dr. James MacKenzie landed in 1893, and in 1898, Dr. Robert Grierson, pastor W. R. Foote, and Duncan MacRae of the Presbyterian Church in Canada joined the mission effort.
McKenzie died a year and a half after his arrival while working in evangelism and medical care at Sorae Church, Hwanghae Province. His efforts led to the organization of the Korean mission church for the Presbyterian Church in Canada () in Wonsan. Pastors William D. Reynolds and Lewis B. Tate arrived in 1892 and organized the Korean mission church for the Southern Presbyterian Church () in Jeolla Province.
In 1889, the Northern Presbyterian Church and the Presbyterian Church of Victoria created The United Council of Presbyterian Missions (), with John W. Heron as chairman, to settle issues over the unification of churches. In 1893, the United Council of Presbyterian Missions became the Council of Missions Holding the Presbyterian Form of Government (, also known as the Council of Missions). Both councils consisted solely of foreign missionaries.
Elections for the first Korean presbyters for the council began in 1900. (Hwanghae), Kim Chong-sà Âp, and I Yà Âng-à Ân (both South Pyongan) were elected as elders that year. In 1901, Kil Sà Ân-chu and were elected as elders. On September 20 of the same year, three Korean presbyters and six ministers, along with 25 missionaries, organized the Council of the Presbyterian Church of Korea (Chosun) () at a missionary council held at the Saemoonan Church in Seoul. Missionary William L. Swallen was inaugurated as the first chairman. However, because the Council of Missions retained jurisdiction over church affairs, the Presbyterian Church of Korea initially functioned only as a fraternal organization. In 1902, was appointed as an elder, and additional elders were elected in 1903.
In 1901, Samuel Moffett established the Pyongyang Theological Seminary and became its first principal. The spread of Presbyterianism was further intensified by the Great Pyongyang Revival of 1907. On June 20, 1907, Kil Sà Ân-chu, Yang Chà Ân-paek, , , Sà  Kyà Âng-cho, , and Pang Kich'ang became the first graduates of the Pyongyang Theological Seminary. That same year, the United Council decided to appoint a party committee member to oversee church affairs for the five local councils of Pyeongan, Gyeongseong, Jeolla, Gyeongsang, and Hamgyeong.
On September 17, 1907, with the approval of four presbyters from the Mission Council, 33 missionaries and 38 presbyters organized the Presbyterian Church of Korea into an independent church. The five local councils were reorganized into the seven sub-presbyteries () of Pyongbuk, Pyongnam, Hwanghae, Chungcheong, Jeolla, Hamgyong, and Gyeongsang. The PCK was also known during this era as the "Independent Council" (). On September 17, 1911, during an assembly at Nammoon Church, Daegu, the Independent Council agreed to establish a General Assembly and convert the seven sub-presbyteries into official presbyteries. On September 1, 1912, the first General Assembly of the PCK took place in Pyongyang. In 1916, the Presbytery of Gyeongsang was divided into the presbyteries of Gyeongnam and Gyeongbuk, and the presbytery of Pyongseo (west Pyongan) was separated from the presbytery of Pyongbuk.
After the Japanese annexation of Korea in 1910, Korean Presbyterians were advised to remain uninvolved in any political cause. As a result, initial relationships between the colonial government and the Presbyterians were peaceful. Missionaries accepted Japanese rule as "the powers that be" and asserted a position of "loyal recognition" of the occupation. Nevertheless, many Korean Presbyterians were suspected by the colonial government of being political agents and were arrested, often without proper explanation or trial. In the 105-Man Incident, a group of Presbyterians was accused of plotting to assassinate then-Governor-General of Korea Terauchi Masatake in Sonchon. Missionaries were also charged with distributing firearms for the alleged assassination plot.
The Government-General of Chà Âsen actively pursued policies aimed at suppressing Christianity. A set of restrictions established in 1915 limited evangelist activities and placed sermons under police scrutiny. The same year, the colonial government further demanded that all schools in Korea discontinue all Bible studies courses within ten years. Tensions between Christians and the colonial government led many Korean Presbyterians, such as Kil Sà Ân-chu, to become closely involved in the March First Movement of 1919.
The persecution of Christians intensified as a result of the movement. Police forces frequently destroyed Presbyterians' properties, and many missionaries were placed under scrutiny. By the end of June 1919, 1,461 Presbyterians had been arrested by Japanese police; within less than four months, the total number of Presbyterian arrests increased to 3,804. 41 of the Presbyterian leaders were killed, and twelve churches were destroyed. Horace Underwood made detailed accounts of the Jeam-ni Massacre during a trip to Suwon with his colleagues.
The March First Movement led to the resignation of Governor-General Hasegawa Yoshimichi on August 4, 1919, and the appointment of Saità  Makoto as his successor. Saità  accepted the Korean representatives' demands and agreed to alleviate restrictions on protests and the press. In September, a complaint documenting the requests of the church to the colonial government, which included an end to the ban on Bible study courses, was drafted among six missionary councils. The complaint was submitted to the Government-General, which accepted the requests.
By 1937, the Presbyterian churches were largely independent of financial support from the United States. Presbyterianism in Korea was reconstructed after World War II, and the General Assembly of the Presbyterian Church was re-established in 1947.
In the 1950s, the Presbyterian Church of Korea suffered from a series of schisms over issues of theology, ecumenism, and worship.
The first of these divisions was connected to a controversy that began in the 1930s, when Korea was still under Japanese rule. At that time, university students were instructed to bow to the Shinto shrine in worship, which was theologically and politically controversial amongst Christians. While many complied, some Christians at Pyongyang Theological Seminary adamantly opposed it, holding that the Bible prohibited such actions. After Korea's liberation from Japanese rule and subsequent division, many northern Koreans relocated to the south. Those who formerly opposed the Shinto shrine worship established a new seminary, Koryo Theological Seminary (now Kosin University) in 1946, and eventually formed a new denomination, the Presbyterian Church in Korea (Kosin) in 1951.
The second division occurred in 1953, when progressives separated to form the Presbyterian Church of the Republic of Korea (KiJang). In the 1970s, the KiJang Presbyterians would produce some of the key leaders of minjung theology, a movement advocating social justice under the dictatorship of Park Chung Hee.
In 1959, at the 44th General Assembly, a third schism divided the Presbyterian Church of Korea into two equal branches: the Presbyterian Church of Korea (TongHap) and the Presbyterian Church in Korea (HapDong). The main issue was whether the Church should be a part of the ecumenical organization, the World Council of Churches (WCC). Park Hyun-nyon, president of the Presbyterian Seminary of the General Assembly, led the formation of the evangelical "HapDong" (the union body), whereas those who supported relations with the WCC formed the ecumenical "TongHap" (the united body). Today, TongHap and HapDong represent the largest factions of Korean Presbyterianism.<section end="1950s Schisms" />
All of these churches have the same confessional basis, the Apostles' Creed and the Westminster Confession.