Proto-Three Kingdoms

Proto–Three Kingdoms of Korea
Korean name
Hangul	원삼국시대
Hanja	原三國時代
Revised Romanization	Wonsamguk Sidae
McCune–Reischauer	Wŏnsamguk Sidae

Proto–Three Kingdoms of Korea (or Samhan) refers to the proto-historical period in the Korean Peninsula, after the fall of Gojoseon and before the maturation of Goguryeo, Baekje, and Silla into full-fledged kingdoms. It is a subdivision of what is traditionally called Korea's Three Kingdoms Period and covers the first three centuries of the Common Era, corresponding to the later phase of the Korean Iron Age.

When Gojoseon was defeated by the Han dynasty of China in 108 BC, the northern region of the peninsula and Manchuria was occupied by the states of Buyeo, Goguryeo, Okjeo, Dongye, and other minor statelets. Goguryeo's traditional founding date is 37 BC, but it was mentioned in Chinese records as early as 75 BC. China installed four commanderies in former Gojoseon territory, but three of them fell quickly to Korean resistance. Goguryeo gradually conquered and absorbed all its neighbors, and destroyed the last Chinese commandery in 313.

In the south, the little-understood state of Jin had given rise to the loose confederacies Jinhan, Byeonhan, and Mahan, or collectively, Samhan. Baekje was founded in 18 BC in Mahan territory and began to slowly overtake it. Silla was founded by the unification of six chiefdoms within the Jinhan, traditionally in 57 BC, although it may have been somewhat later. Byeonhan was absorbed into the later Gaya confederacy, which in turn was annexed by Silla.

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