The Current Status and Characteristics of ‘Stronghold for Protection in Fortresses and Islands’ Built in Jeollanam-do during Goryeo Dynasty’s Wars against Mongolian Invasion
Authors:   The Paek-San Society, Kim Sejong 
Published: May 2024

The purpose of this study is to examine the current status and characteristics of the remains of strongholds for protection in fortresses and islands utilized in Jeollanam-do during Goryeo Dynasty’s Wars against Mongolian Invasion, focusing on the remains of that period investigated in that region so far.
As is well known, Goryeo’s strategy for resisting the Mongolian invasion was to build strongholds for protection in fortresses or islands since the wars against Mongolian invasion began in August 1231 (the 18th year of King Gojong’s reign). These two strategies were implemented throughout the nation following the transfer of the capital to Ganghwa carried out by Choi Woo. In that respect, in Jeollanam-do, fortresses for protection were built on rugged mountains in the inland area, and strongholds for protection on islands including castles were built on islands adjacent to the coastal area of the southwestern coast. In particular, after 1253 (the 40th year of King Gojong’s reign), the Mongolian army began attacking islands in the southwestern coastal area of Jeollanam-do in response to Goryeo’s strategy of building strongholds for protection on islands. Nevertheless, Goryeo achieved the expected results in the battles of Jangseong Ibamsanseong fortress and Shinan Aphaedo, Jeollanam-do by effectively using the strategy of building strongholds for protection on fortresses and islands. These results seem to have originated from the activities of Banghobyulgam, who played a key role in the implementation and operation of the strategy of building strongholds for protection, as well as the strategy of building strongholds for protection in fortresses and islands implemented with meticulous planning after the transfer of the capital to Ganghwado.
On one hand, the reality of the strategy of building strongholds for protection on fortresses and islands carried out in Jeollanam-do during Goryeo’s Wars against Mongolian Invasion has made it possible to understand specifically about building strongholds for protection on islands rather than fortresses. Fortresses for protection built in the inland area shows significant differences from ancient fortresses in terms of location, scale, and structural characteristics. However, it has something in common with fortresses for protection in Gangwon-do and central inland areas. On the other hand, Jindo Yongjangseong itself has great implications in that Yongjangseong, which was used as the center for the wars against Mongolian invasion, is fortress similar to a castle town built in consideration of the geographical characteristics and geopolitical position of an island.
Yongjangseong consists of Yongjangsanseong fortress, which is a large-scale stone fortress spanning 13km, and a palace built using an existing mountainous Buddhist temple. The spatial structure of Yongjangseong fortress is understood to be a new castle town structure that combines the locational characteristics of an island and the spatial structures of Gaegyeong or Ganghwa based on the fortress for protection built under the plan of the Ganghwado government. This fortress began to be built according to the strategy of building strongholds for protection on islands carried out after the transfer of the capital to Ganghwado, and was finally completed following the transfer of the capital to Jindo.
In this regard, attention is paid to roof tiles with an inscription 「Master artisan Hyein the 3rd month of Gyemyo (Guimao in Chinese) year」 and roof tiles showing an isomorphic or homogeneous set relationship, which are found simultaneously in Yongjangsanseong fortress and major islands along the southwestern coast.