NOT KNOWN FACTS ABOUT KOREA

Goryeo was invaded by the Mongols in seven big strategies in the 1230s until finally the 1270s, but was never ever conquered.[117] Fatigued just after many years of fighting, Goryeo sent its crown prince towards the Yuan money to swear allegiance into the Mongols; Kublai Khan recognized, and married amongst his daughters on the Korean crown prince,