The Tang Emperor's Right-Hand Man: Taking the Heavenly Khan as a Minion

In the second month of the sixth year of the Kaihuang era of the Great Sui dynasty. That year, Chang'an was still called Daxing City. That year, the Great Sui had yet to conquer Southern Chen and unify the realm. That year, Crown Prince Yang Yong was still in the emperor's favor, while Prince of Jin Yang Guang was only beginning to bare his fangs. That year, Li Yuan, the future Emperor Gaozu of Tang, was only twenty years old, and the Son of Heaven had yet to be born.