Baekje: Notes

The Foundation of the Kingdom of Baekje

The principal Korean source for the polity, the 12th-century Samguk Sagi, asserts that Baekje was founded in the 1st century BC, but there is no corroboration in the contemporary Chinese chronicles which could hardly overlook the emergence of a new polity on the Korean peninsula. Unlike Goguryeo or Buyeo, Baekje is not mentioned in the Book of the Later Han (Hòu Hàn shū|後漢書) among the polities in and around Korea, implying that it did not exist before the fall of Han (220 AD) — at least not as a separate entity of note.

The earliest mention of Baekje in Chinese sources is likely the Baekje guk (伯濟國|백제국), listed as a member of the Mahan confederation (馬韓|마한) during the 3rd century AD. The connection between the two homophonous entities is made explicit when Baekje is said to have been a dependency of Mahan which itself is last mentioned in 286 AD when 11 of its constituents were trading with the Empire of Jin. The first mention of Baekje with its modern spelling as a separate polity in contact with both Japan and Jin is dated to the 4th century.

In the 7th-century Chinese histories the foundation of Baekje is explicitely placed in Dàifāng (帶方) in Central Korea and credited to Gutae or Gui (仇台|구태/구이), whom one Chinese source indirectly misidentifies as Wigutae or Wigui (尉仇台|위구태), a king of Buyeo who predated the establishment of Dàifāng and who had no known connection to the central peninsula. This association with Dàifāng, if taken literally (along with the identity of the two Baekje), would put the foundation of Baekje (a) to after 204 (as Dàifāng itself was not established before that year), (b) likely to after 245 (when a governor thereof is mentioned in Chinese chronicles).

The comparably late Chinese historical text, Tongdian (Tòngdiǎn|通典) does not mention the founder of Baekje by name, merely speaking of descendants of the said Wigutae of Buyeo. The ruling family did indeed claim descent not only from Buyeo (扶餘|부여) but also from the mythological Dōngmíng (東明) who is also known as Chumo (鄒牟|추모). The connection with Buyeo was manifested in its use as their surname — at least in Chinese contexts — as early as 372. Some sources instead say that Baekje originated from Goguryeo (Chinese: Gāolí guó|高麗國), which is in turn said to originate in Buyeo, or from Suǒlí guó (索離國).

The Samguk Sagi offers three foundation stories. In the first version, the founder of Baekje is called Onjo (溫祚|온조), stated to be a younger brother of Biryu (沸流|비류) and the son of Chumo (Dōngmíng) who is also claimed as the founder of Goguryeo. The foundation itself, thus tied to early Goguryeo and explicitely dated to BC 18, is then explained as the result of an emigration of the brothers (and their retainers) after the death of their father and succession by an elder half-brother. In the second version, the same two brothers are named the sons of Utae (優台|우태), of the royal family of Buyeo. Here the elder Biryu becomes the founder of Baekje. As a third option, the Samguk Sagi cites the Chinese chronicles with Gui as the founder.

Despite professing not to know which of the presented information is correct, the compiler of the Samguk Sagi opted for the 'Onjo version,' according to which Baekje was founded in the 1st century BC, and thus needed to fill the resulting period before the mid 4th century, i.e. before the Chinese and Japanese sources start to provide corroboration. The list of kings includes 12 monarchs supposedly ruling between BC 18 and 346 AD. Closer scrutiny, though, makes this chronology rather implausible. Onjo and his six descendants and successors, together spanning 252 years (BC 18 to 234 AD), seem to have been added later so as to cover the (presumed) temporal gap between the founding date postulated in the 'Onjo version' and the early 3rd century AD. The next five kings (reportedly ruling AD 234 to 346 and connected with the 'Gui version'), though somewhat more plausible, are not corroborated in Chinese or Japanese sources.

Archaeology, finally, seems to also point to between about 250 AD and 300 or maybe 350 as the founding time of Baekje.

Starting with the reign of Chogo wang (肖古王|초고왕) [346-375], the years given in the Samguk Sagi are largely corroborated by the Nihon Shoki and at least indirectly by Chinese official histories. Considering, however, the suspicious pattern of months of death as given in the Samguk Sagi (cf. Best 2006, p. 32), the earlier Chinese and Japanese sources have been generally preferred in the record over the dates given in the Samguk Sagi whenever there is disagreement.