 When Emperor Xuan died, Northern Zhou's successor state, Sui China, had been attacking Chen, but upon hearing about Emperor Xuan's death, Emperor Wen of Sui (Yang Jian) decided that it was improper to attack a state that had just lost its emperor and withdrew his forces.He also sent ambassadors to mourn Emperor Xuan's death, and his letter to Chen Shubao referred to himself by his personal name—a sign of humility.However, Chen Shubao's return letter included the sentence, "May it be that when you govern your state, all things can be well, and that between heaven and earth, there will be peace and quiet."