A Study On The Consciousness And Policy Of The Northeast Boundary During The Reign Of King Sejong Of The Joseon Dynasty

From the Reign of King Jujong of Goryeo dynasty to the reign of King Sejong of Joseon Dynasty,the northeast boundary of the two dynasties was transformed.After more than 300 years and 23 generations of Kings of the two dynasties,the northeast boundary was finally completed with the Tumen River as the border in the Reign of King Sejong.In this process,Kim Jong-seo,a powerful official during the Reign of King Sejong of the Joseon Dynasty,played a crucial role.His <the letter which discuss fortification at Xingcheng four towns or not> that he wrote to King Sejong was a summary of the northeast boundary issues faced by the two dynasties and a plan for the next stage of the boundary policy before the Goryeo period to the Reign of King Sejong of the Joseon Dynasty.Through the analysis of the letter,we can sort out the evolution of the border consciousness.For the understanding of the northeast border,everything started from the so-called restoration of the old land of Goguryeo.After the temporary success of the restoration of the old land failed,the restoration of the old land thought gradually became the mainstream,which lasted until the end of the Goryeo Dynasty.Early in the north dynasty,because of the northeast frontier is general yi sung gae and the rise of family and land,the thought of "fathers" gradually occupied the main part of the consciousness,consciousness anyway integration development,always inseparable from the "development" and "after" two core topics,and swing between them,which is ultimately in the sejong period,In line with the "great justice",the "restoration of border" consciousness combined with the "restoration of the old land of Goguryeo","restoration of the old land of the Dynasty" and "ancestors,the land of origin" together constituted the boundary consciousness of the Sejong period.From the beginning of the Sejong period,the Joseon Dynasty had a complete consciousness of possession of the northeast border of Korea.However,with the obvious change of ideology,there is always a gap in boundary policy.Under The obvious change of ideology,the northern invasion policy of Emperor Ruizong of Goryo dynasty has been successful for a short time.However,with the obvious change of Yin guan,nine cities,and the obvious change of Yuan dynasty,the actual territory in northeast Goryo has not been able to reach the scope of ideology.Ready and we need a series of policies to make the boundaries of the period of king moved to overthrow the yuan Ming dynasty,the Ming and the boundary of the policy to retreat,always with the heart of the "barriers" to treat the ethnic group living in the frontier region,but because the suzerain directly conferring the local ethnic relations,such as north Korea dynasty extension steps have been stuck,until the sejong period,Seizing the opportunity of The death of Momo Timur,Kim Jong-seo set up six new towns and pushed the border to the tumen River,and the scope of the northeast of Korea reached the scope of consciousness.Consciousness pushed forward the policy,and after the integration of the two during the Reign of King Sejong,the success of the policy also deepened the consciousness.Since then,both the actual boundary and the conscious boundary have reached the tumen River line,to some extent,as the extension of the "pioneering" thought,the Korean dynasty’s consciousness of the northeast boundary even exceeded the Tumen River,and this understanding has far-reaching influence.