Hong Taiji, the second khan of the Later Jin dynasty conquered the Northern Yuan dynasty of the Mongols in 1635. He started to use the Mongolian title "Boγda Sečen Qaγan" ("Bogda Chechen Khan"), and he once called himself "Bogda Khan" in letters to upper-class figures in Mongolia and Tibet.
Hong Taiji, ruler of the Later Jin dynasty, successfully conquered the Mongol Northern Yuan dynasty in 1635. He started using the Mongolian title "Boγda Sečen Qaγan," which he also referred to as "Bogda Khan" in letters to influential individuals in Mongolia and Tibet.