THE TERRITORIAL EXPANSION PROCESS OF GOGURYEO IN THE 5TH CENTURY

Abstract

Goguryeo (1st - 7th century) was one of the kingdoms established in the northern part of the Korean Peninsula during the Three Kingdoms period. The kingdom of Goguryeo experienced significant growth in the 5th century under the reign of King Gwanggaeto (391-413) and King Jangsu (413-491), who intensified policies aimed at territorial expansion. These policies included northward expansion to secure a route into the mainland by occupying the Manchuria region, and southward expansion to reduce the territories of Baekje and Silla while extending control over the western seas, thereby affirming its sovereignty. Employing historical and logical methodologies, this article elucidates the critical foundations that enabled Goguryeo to expand its territory and the execution of this policy in the 5th century. Additionally, the article clarifies the complex international relations in Northeast Asia in general, and the Korean Peninsula in particular, during the 5th century. Consequently, the article draws scientific conclusions about the impact of territorial expansion policies on the development of each ancient nation on the Korean Peninsula specifically, and on the world at large.