EVERYTHING ABOUT KOREA

Goryeo was invaded because of the Mongols in 7 important campaigns in the 1230s until finally the 1270s, but was never ever conquered.[117] Fatigued just after many years of battling, Goryeo despatched its crown prince to the Yuan capital to swear allegiance towards the Mongols; Kublai Khan acknowledged, and married among his daughters on the Korea