The Transformation of the Border Between Baekje and Silla in the Early~Middle 7th Century

In this paper, the struggle of Baekje and Silla from the first half of the seventh century to the middle, and the corresponding trend of border transiton were reviewed. First, I examined the Nakdonggang River basin in eastern North Jeolla Province. Silla was blessed with Daegaya in 562 and destroyed the Unbong Plateau. Silla built the Amak Fortress and Sota Fortress etc to pressure Baekje. Thus, King Mu(r. 600~641) attacked the Amak Fortress[located in Unbong-eup] in 602.8, but was defeated by the Silla army. Baekje attacked the Amak Fortress again in the 17th year of King Mu(616). Baekje led the battle of the Amak Fortress to victory, crossed the Palliangchi Head to the east, and won 6 Fortress including the Sokham Fortress[Hamyang-gun] of Silla in 624.10. Afterwards, Baekje tried to advance from Hamyang-gun to Hapcheon-gun through Anui-myeon and Geochang-gun. In 642.7, King Uija(r. 641~660) took a soldier and occupied 40 Fortress, including Mihu Fortress. Finally, Baekje occupied Deya Fortress[Hapcheon-gun] in 642.8. Silla lost its stronghold on the Nakdong River front, defending the capital city, by losing the battle of Deya Fortress. Queen Sundeok(r. 632~647) wanted to use Kim, Yu-shin as a general[軍主] to prevent the attack of Baekje. Kim, Yu-shin turned the defensive situation into an offensive enemy and led the military to attack 7 Fortress including Gahye Fortress in 644.9. As a result, the Gahyejin[Ugok-myeon·Gaejin- myeon, Goryeong-gun] was opened in the Nakdong River basin. Baekje lost even in the Battle or Maeripo Fortress[Chilbuk-myeon, Haman-gun], eventually failing to cross the Nakdong River. Baekje continued its offensive in the direction of the Chupungyeong Route. The place where the two countries had become a watershed for each other was Gajam Fortress[Yangsan-myeon, Yeongdong-gun]. Baekje and Silla fought three battles between 611~628 over Gajam Fortress. In the end, Silla occupied the Fortress. As long as Silla occupied Gajam Fortress, it was impossible for Baekje to attack Silla in the direction of Yeongdong~ Geumsan-gun. The clash between Baekje and Silla took stable phase and was reenacted in the 655 Battle of Jocheon Fortress[Yangsan-myeon, Yeongdong-gun]. Baekje and Silla fought 2~3 battles here. Silla occupied Jocheon Fortress and secured a foothold in Yeongdong~Geumsan-gun to advance to Sabi, the capital of Baekje. King Mu's offensive against Silla was also carried out in the direction of Mhju~Gimcheon in Na·jetongmun Route. In 636.5, Baekje general Uigik was stationed in Okmun valley[Gaya-myeon, Hapcheon-gun] to attack Doksan Fortress[Seongju-gun] with 500 soldiers, but was attacked by Silla troops and all died. In 646.10, King Uija sent a general Uigik to besiege Musan Fortress[Mupung-myeon, Muju-gun] in Silla and attacked Gammul Fortress[Gimcheon-si] and Dongjam Fortress[Gimcheon-si]. However, the Baekje army was completely destroyed by the attack of the Kim, Yu-shin unit. Kim, Yu-shin also won the Battle of Deya Fortress and Okmun valley in 648.4. Kim, Yu-shin won a series of battles that lasted until 649, killing more than 30,000 Baekje soldiers and capturing more than 10,000. With this, Silla was able to turn the situation of Baekje into an offensive enemy. The victory of the Battle of Jocheon Fortress in 655 signaled the imminent advance to Sabi's capital.