The Catholic community of Jeju began its official evangelization and liturgical life on May 26, 1899. Yet historical evidence shows that the Good News had already reached the island much earlier. In 1592,during the Japanese invasions of Korea, Kim Bok-su returned to Jeju from Japan together with European envoys, bringing with him Catholic catechisms and prayer texts, which introduced the faith to the island. In 1653, the Dutch castaway Hendrick Hamel was shipwrecked on Jeju; passages in his book Hamel’s Journal confirm that he was a Catholic.

The faith on Jeju was sustained through the sacrifices of martyrs. 정난주 마리아(Maria Jeong Nan-ju), wife of 황사영 알렉산더(Alexander Hwang Sa-yeong), fled to Baeron in Jecheon during the 1801 신유박해(Shin-yu Persecution), where Hwang wrote the “Hwang Sayoung Letter,” appealing for aid in the face of brutal persecutions. The letter was intercepted before delivery; Hwang was executed by dismemberment outside Seosomun in Seoul. Jeong Nan-ju was exiled to Jeju, lived as a government slave, and died of illness in1838. Around the same period, 홍낙임(Hong Nak-im), the son of Hong Bong-han and relative of the royal family, had embraced the faith during the 1791 신해박해(Shin-hae Persecution). During the Shin-yu Persecution he was exiled to Jeju as a leading “heretic” and eventually martyred by poison.

The first Jeju-born Catholic to be baptized was 김기량 펠릭스 베드로(Felix Peter Kim Gi-ryang). A fisherman, he was shipwrecked during a storm in1856 and drifted to China, where he met a Korean seminarian and was baptized. He returned to Jeju with Catholic books from Seoul and evangelized many people. In the 1866 병인박해(Byung-in Persecution), he was captured while attempting to baptize new believers near Tongyeong and was martyred by having iron spikes driven into his chest. The Diocese of Jeju continues to pray for his canonization.

A decisive figure in the full establishment of the Church on Jeju was 양용항 베드로(Peter Yang Yong-hang) of Saekdal-ri, Jungmun. After being baptized on the mainland, he sought to bring priests to the island. His efforts succeeded, and with the arrival of clergy to celebrate the sacraments, a formal community was established in 1899. That same year, Bishop Mutel of the Joseon Diocese officially founded the Jeju Parish and sent Father Peynet of the Paris Foreign Missions Society as pastor, with Father Kim Won-yeong Augustine as assistant.

By early 1901, strong missionary activity had led to over 240 baptisms and 700 catechumens. That year, however, the Shinchuk Persecution erupted, and more than 700 Catholics and civilians were massacred at 관덕정(Gwandeokjeong). The bodies of the martyrs were buried near Hwabukcheon, and in 1903 the royal court designated wasteland near Ara-dong as their burial site—today’s 황사평 성지(Hwangsapyeong Shrine).

During the Japanese occupation, churches were closed and clergy and religious were imprisoned, yet after liberation the missionaries of the St. Columban Foreign Mission Society rebuilt the Church with vigor. During the Korean War, they strengthened the local community through relief work for refugees and residents. In 1962, Father Patrick James McGlinchey founded the Isidore Rural Development Association and operated the Hallim Livestock Station, establishing a foundation for modern livestock farming. He also founded St. Isidore Clinic, greatly contributing to both agriculture and medical care.

In 1971, ecclesiastical jurisdiction for Jeju was separated from the Archdiocese of Gwangju and established as the Jeju Apostolic Prefecture, which was elevated to a full diocese in 1977. Since then, Jeju has continued to develop through social ministries such as the founding of St. Joseph Nursing Home (1986), the introduction of the Little Brothers of Jesus(1992), and the pastoral programs of the Salesian Sisters (1994).

Today, the Diocese of Jeju comprises 25 parishes and 11 mission stations, served by 46 priests (including one Columban missionary and two religious priests), around 120 religious, and approximately 58,000 Catholics.