Wang had requisitioned the forces of Korean tribes within the borders of Xin-controlled territory when he began his campaign against Xiongnu.

The Korean tribes had refused, and marched beyond the borders; the army that Wang sent against them are defeated.

The general Wang had sent, Yan You, had used humble words to deceive their leader, Zou, who carries the title the Marquess of Gaojuli, (Goguryeo, but apparently having no direct connection with the contemporary Kingdom of Goguryeo), into a meeting with him, and then killing Zou by surprise.

Wang then changes Gaojuli to the derogatory term "Xiajuli" (gao means "high", while xia means "low"), which further enrages the Koreans, causing them to attack the Xin northeastern regions with greater ferocity.