The Goguryeo Kingdom was founded in 37 B.C., and by the first century, it had firmly established itself as a powerful state. Koguryo developed into a powerful nation and acted as a bulwark against the aggressive northern nations and China. During this time, the kingdoms of Paekche and Shilla developed rapidly. This increased friction between the Three Kingdoms. These Three Kingdoms were unified by the last of the developed kingdoms, Shilla, thereby marking the first national unity. On the other hand, in Manchuria, the old cradle of Koguryo, Parhae was firmly established and undergoing distinct development. The Three Kingdoms developed as aristocrat-centered societies, and the aristocrats became the leaders of the culture. The Three Kingdoms accepted Buddhism, which greatly advanced and expanded the scope of their culture. In this way, the Three Kingdoms developed a colorful and refined aristocrat-centered Buddhist culture which was eventually introduced to Japan and greatly influenced the development of its ancient culture.

Silla Kingdom (B.C.57~A.D.935)
The Silla Kingdom was founded in 57 B.C., Silla was located in the southeastern part of the Korean peninsula. In its early days, Silla was the weakest of three kingdoms in existence, but later became powerful enough to unify them under its rule in 676. After unification, Silla traded vigorously with foreign countries. General Jangbogo established Cheonghaejin on Wando Island and swept the pirates from the seas and led the overseas trade of East Asia Sea.   

Goguryeo ( Koguryo ) Kingdom (B.C.37~A.D.668)
The Goguryeo Kingdom was founded in 37 B.C., and by the first century, it had firmly established itself as a powerful state. Goguryeo covered large parts of present-day Manchuria. The country was not only the most powerful and most aggressive kingdom of three kingdoms in existence (Baekje and Silla being the other two) but also the most powerful in Northeast Asia in the 5th century. King Gwanggaeto the Great (375-413), in particular, conquered the largest territory in the entire history of Korea.

Baekje ( Paekche ) Kingdom (B.C.18~A.D.660) 
The Baekje Kingdom was founded in 18 B.C., Baekje was located in the southwestern part of the Korean peninsula and was one of the most advanced nations at that time. Baekje had the closest communication with neighboring Japan and exerted great influence on various fields of Japanese culture, sending many craftsmen, artisans, tailors, tile makers, and scholars to that country