Koryo
The Emperor of Koryo accepted the Emperor of the Rising Sun's fealty, and in return for their loyalty, he gave them peace with their neighbors. A good tradeoff, if you acks the historians.
That is simply a sidenote, however, to the real goods of what this story is about.
In the midst of Koryo's JugguhNOTaughts, there started a cult. This cult was that of the battle god, Lu Bu. This cult had started a few hundred years ago, and had risen to prominence between the captains of the army.
This may have been one of the reasons that the JugguhNOTaughts were such good killers on the battlefield. There was a legend within the cult that a young man would come and prove himself on the battlefield to be the reincarnation of Lu Bu, and would bring even more power to Koryo. Who knows when this prophicy would come true?