The Jin Yi Wei was a special official position in the Ming Dynasty, with the Jin Yi Wei Commander-in-Chief responsible for the safety and protection of the emperor and the palace. Established during the Yongle reign of the Ming Dynasty, the Jin Yi Wei initially consisted of a group of loyal military generals and attendants who formed a secret police force, which gradually developed into a specialized organization composed of selected officials and military personnel.
Members of the Jin Yi Wei usually wore brocade clothes and carried swords, hence they were known as "Jin Yi Wei Pei Dao" (Jin Yi Wei carrying swords). The Jin Yi Wei carrying swords was a symbol of their identity and one of the weapons they needed for their daily work. During the Ming Dynasty, the sword was a symbolic weapon rather than a practical combat weapon. The Jin Yi Wei sword was usually a single-edged short knife, shorter than the general long knife, making it easier to carry and use.