I having been showing my Koreans here since my pioneer Joseon customs, so I thought I'd better make a brief introduction to their historical background (parts extracted from Wiki);
The Japanese made a sneak attack on Korea in 1592 and a second attempt in 1598 but were repelled both times by Joseon (Korea's longest dynasty) army with Hideyoshi losing half of his Samurai army with each invasion.
Here are some some these relatively simple Joseon soldiers, guarding a peaceful nation of farmers and artisans against civil-war-hardened samurai armies, many armed with the western arquebus.