History During the
Three Kingdoms period, Korea was divided into three kingdoms (
Goguryeo,
Paekche,
Silla) and one confederacy of smaller kingdoms (
Kaya). Goguryeo, a kingdom that was built by Prince Chumong (
King Dongmyeong) of
Buyeo alongside the
native Koreans in the ruins of
Old Chosŏn, expanded its territories southward, overthrowing and absorbing the
Four Commanderies of Han that were established after the
Han dynasty invaded and destroyed Old Chosŏn. The kingdom reclaimed most of the lost lands from the Han by the early 4th century and successfully repelled incoming invasions from the Chinese dynasties. Paekche was a kingdom that arose from an earlier confederacy (
Mahan confederacy) that was part of the
Samhan period of Korea. It is said that King Dongmyeong's second son,
Onjo moved to Mahan and united the people there to create a new kingdom. Paekche became a powerful naval kingdom that had good diplomatic ties with Japan. Kaya was a confederacy that succeeded its former polity known as the
Byeonhan confederacy, it was the only region in Korea that did not become a single nation, but remained as a key trading hub for kingdoms in East Asia. The confederacy was composed of smaller kingdoms, but was unilaterally managed under the leadership of
Geumgwan Gaya. Silla was built under the leadership of
Hyeokgeose who united the old kingdoms of the
Jinhan confederacy into one. It was considered relatively small and had rivalries with its neighboring kingdoms such as Paekche. It mostly depended on bigger kingdoms such as Goguryeo in its earlier years, and later the
Tang dynasty. However, the kingdom quickly resisted its allies once they were deemed unprofitable (i.e.
Silla–Tang War), and ultimately became the first kingdom to
unify the peninsula in Korean history. Outside of Korea, Japan (known as
Wakoku) became heavily invested in Korean affairs due to trade and cultural dependence. Prior to the establishment of the
Yamato Kingship, Wakoku (as well as the Korean kingdoms) was considered as a "primitive" or "barbaric" nation by the Chinese (see
Dongyi), hence being given the characters "
Wa (倭)" which meant "dwarf" or "small", and "Koku (國)" which meant "nation". Korean kingdoms did not share the same sentiment as the Chinese, instead deeming Wakoku as a valuable trading partner as well as a culturally compatible nation. Many new technologies were passed over to Japan through
Toraijins from the kingdoms and provided Japan with cultural enlightenment such as
Confucianism,
Buddhism,
Chinese characters (
Kanbun/
Kanji),
medicine,
lunar calendar, and cultural practices such as
Sue ware production and weaving. Wakoku also understood the importance of the Korean kingdoms at the time, thus forming alliances with them and providing military support in exchange for their knowledge.
Premise of the war During the late 4th century, friction between the kingdom of Silla and the confederacy of Kaya was beginning to emerge since the fall of the
Lelang Commandery caused by Goguryeo. Prior to this, the two kingdoms' predecessors: Byeonhan and Jinhan, were known to show a strong sense of rivalry despite being recorded as "culturally and ethnically almost identical" by Chinese historians. This sentiment is believed to have been carried over even after the two confederacies evolved into newer polities. The confederacy, known for its production of
iron, often traded with the neighboring Korean kingdoms, as well as the Chinese Lelang Commandery and the Japanese Wakoku or "Wa". However, after the fall of the commandery by Goguryeo forces, Kaya lost an important trading partner. Silla, which was considered as the least influential kingdom at the time, was able to create an alliance with Goguryeo which opened up a new gateway for trade routes that expanded into the bigger continental regions rather than being confined within the peninsula. Sensing the threat and having pre-existing rivalry with Silla, Kaya in turn allied with Paekche and Wa of Japan, and attacked Silla for dominance over the region of southern Korea. == Kaya–Silla War ==