Following the fall of the Sui dynasty (581-618 CE), the new Tang dynasty (618-907 CE) , under Emperor Gaozu, and Koguryŏ tried to repair their relations, which were very hostile during the Sui Dynasty. While trying to repair their relationship, Gaozu sent an envoy which told Koguryŏ he would not make it another outer vassal of China because it would make Koguryo seem more important that the other kingdoms of Korea.{1} Tang China wanted to remain neutral in Korean affairs under Emperor Gaozu. However, as this was going on, tensions in Korea started to rise between Koguryŏ, Silla, and Paekche, the three kingdoms of Korea. Each kingdom wanted to unite Korea under their rule, but the only way to do that was to receive help from Tang China. Instead of picking sides, Tang China maintained its neutrality by mediating disputes between the three Kingdoms over petty disagreements and rumors of border expansions. Tensions between the Kingdoms increased as Emperor Taizong took the Chinese throne in 626.{2}Taizong was eager to regain Koguryŏ after the Sui-Koguryŏ wars and invaded the kingdom in 646. Silla saw this as an opportunity to gain China as a powerful ally who would help them unite the nation. Eager for their support, Silla invaded southern Koguryo with 50,000 troops, which prompted the alliance against Koguryŏ and Paekche who were enemies of Silla.{3} Tang China and Silla made a plan to take Paekche and then to attack Koguryŏ from the north and south. In return for their services, Silla would receive the lands south of Pyongyang and the territories of Paekche.{4} The plan was put into action in 660 under Gaozong.{5} At the time of the invasion, Paekche had very close ties with Japan. The Japanese sent 30,000 soldiers on the Kum river to guard Paekche. But they were ultimately defeated by the Silla and Tang navy.{6} Paekche fell in 663 and Koguryŏ in 668. This small moment showed Koreans that Japan would not support the Tang wars, and intensified migration to Japan from Korea.
When they migrated, the Koreans brought with them more than just the clothes on their backs. They brought their skills, culture, writing, and religion with them. Although, Korea has always been a way of entry for Buddhism in Japan, the transfer of Buddhist beliefs intensified in Japan during this time period. In the 700s, Buddhism started to become a large influence on the courts of Japan. The first constitution of Japan, possibly written by Shotoku Taishi, highlighted prominent Buddhist and Confucian beliefs. This shaped how the Japanese government would be run in the future.
References:
{1} Zhenping Wang, Tang China in Multi-Polar Asia: A History of Diplomacy and War (University of Hawai’i Press 2013), 56.
{2} Wang, Tang China in Multi-Polar Asia, 56-57.
{3} Wang, Tang China in Multi-Polar Asia 71.
{4} Wang, Tang China in Multi-Polar Asia, 72.
{5} Jinwung Kim, A History of Korea: From “Land of the Morning Calm” to States in Conflict, ( Bloomington Indiana University Press 2012), 51.
{6} Kim, A History of Korea, 52.
Bibliography:
Kim, Jinwung. A History of Korea: From “Land of the Morning Calm” to States in Conflict.” 51-52. Bloomington: University of Indiana Press, 2012.
Wang, Zhenping, “Restoring Lost Glory in Korea: China, Koguryo, Silla, Paekche, and Parhae.” Tang China in Multi-Polar Asia: A History of Diplomacy and War, 56-72. University of Hawai’i Press, 2013.
