With the end of WW2 korea was one of a whole. Until USA and Russia established a line through it. Soviet Union in the north and USA in the south. Both wanted korea to be a whole but neither would give up a side.
An interest is whant if to know more about something like plants or rocked
Hopes this helps and if needed I can explain further
Christianity is the most widely practiced in europe
Both Europe and Japan had a "cast system" you could say, where peasants worked the land that the nobles owned. (The Japanese had their own terms for the people, I just can't remember them.) During this time, Europe had knights and these Knights had a code called Chivalry. Over in Japan, there were Samurai with a very similar code which was called Bushido. Hope this helps.