The bandit groups that have emerged for the longest time in Korean history are Japanese pirates
The Japanese invasion of the Korean Peninsula has a long history, and it has continued for 1,500 years from the early Silla period to the mid-Joseon period

However, if you look at the records of Japanese pirates who entered the late Goryeo Dynasty, you can see the opposite of the Japanese pirates portrayed like that
Battle of Huangshan, where Goryeo Army and Japanese pirates fought in 1380, says the commander of the Japanese pirates, Azibaldo, wore armor all over his body, leaving no space for arrows, and the Japanese invasion of Goryeo in 1377 was armed with armor that covered his hands and feet, and then ran forward on horseback, according to the Goryeosa






In other words, it is appropriate to see Japanese pirates as not just a band of drab bandits, but an elite combat unit that even had heavily armed cavalry, where both humans and horses wore armor