Transition under Ambiguity: Koryǒ-Mongol Relations around 1260

The rise and expansion of the Mongol empire in the first half of the thirteenth century created a serious crisis in the tributary (冊封-朝貢) system, which had been providing a feasible framework for five hundred years for exchange between the mainland regimes like the Tang, Song, Khitan Liao and Jurchen Jin, and those on the Korean Peninsula including the Silla and Koryǒ, which allowed the latter de facto independence while ritually recognizing the suzerainty of the former. Despite the Koryǒ’s efforts for continuing the tributary system, the Mongols, imposing its own policies on the newly subjected countries,kept requiring the Koryǒ to fulfill a set of demands, or the “Six Obiligations”