He also approved a decree recognizing the martyrdom of Conventual Franciscan Father Francesco Zirano, an Italian priest killed in Algeria in 1603.
The pope's approval of the martyrdom decrees Feb. 7 opened the way for the martyrs' beatifications on a date yet to be announced. A miracle is required before any blessed may be canonized.
The Korean cause, referred to as the cause of Paul Yun Ji-Chung and 123 companions, recognizes the sacrifices of those killed for their faith between 1791 and 1888. More than 10,000 Catholics in Korea were killed during that period, starting in 1785.
Blessed Pope John Paul II declared Paul Yun and his companions "servants of God" in 2003. He already had canonized Father Andrew Kim and 102 other Korean martyrs during a trip to South Korea in 1984.
While no date has been set for beatification of Yun and his companions, the Vatican has said it is studying the possibility of Pope Francis visiting South Korea, perhaps in mid-August to coincide with the celebration of Asian Youth Day in Daejeon.
On Feb. 7, the pope also approved three other decrees, recognizing the Mexican founder of a religious order, an Italian Franciscan priest and a Spanish nun for having lived the Christian virtues in a heroic way and declaring them "venerable." Recognition of a miracle attributed to each candidate's intercession is needed before beatification.