• 1784
• The Birth of the Korean Church
• Peter Yi Seung-hun was baptized in Beijing in the spring of 1784 and returned to Korea. This marked the beginning of Catholicism in Korea — started by Koreans themselves, not by missionaries.

• 1780s–1790s
• The Age of Home Churches
• With almost no priests or churches, believers gathered in their homes, prayed together, and taught their families. Homes became the first churches in Korea.

• 1801
• The Sinyu Persecution (The First Major Persecution)
• Many early leaders such as Augustine Jeong Yak-jong and Augustine Yu Hang-geom were martyred. Fr. Zhou Wenmo, the first Catholic priest to enter Korea, was also killed during this persecution.

• 1839
• The Gihae Persecution (A Second Wave of Suffering)
• More believers, including many women and family members, were arrested and executed for their faith. French missionary Bishop Imbert and two companion priests were also martyred.

• 1866
• The Byeongin Persecution (The Most Brutal Suppression)
• An estimated 8,000–10,000 Catholics were killed or imprisoned, and the Korean Church faced its greatest crisis. Despite this, believers continued to practice their faith in secret.

• 1925–1984
• Beatifications and Canonizations
• Korean martyrs were declared Blessed and Saints in stages: 79 martyrs were beatified in 1925, and 24 more in 1968. In 1984, Pope John Paul II canonized the 103 Korean Martyrs in Seoul — the first canonization ceremony held outside Rome since the Middle Ages.

• 2014
• Pope Francis Beatifies 124 Korean Martyrs
• During his visit to Seoul, Pope Francis beatified 124 additional martyrs including Blessed Paul Yun Ji-chung, Korea's first recorded martyr, at Gwanghwamun Plaza.