Korean scholars' rigorous studies on the Korean War increased in the period after the 1970s. The traditional explanation prevailed over the academic circle in the late 1970's. But in the 1980's the revisionist interpretation began to dominate a group of junior scholars. Confronted with the expansion and growth of revisionism, a group of traditionalists organized their academic circle in the late 1980's. The debate between traditionalism and revisionism brought to emerge the post-revisional synthesis based on revisionism or traditionalism plus archive in the early 1990. A new trend of the post-Cold War era after the 1990's is a multi-archival research which was made possible by Soviet archives and Chinese documents. The debate on revisionism and traditionalism was revitalized within academic circles through this post-revisional multi-archival method. To liquidate the past and to meet the clean future, oral history is very important.