This study examines Silla's perception in 643 of the continuity of the wars leading to the falls of Baekje and Goguryeo and the relationship between the handling of the aftermath of their downfall in 660 and 668-669. It also studies Silla's perception of the unification of the Three Kingdoms through the implications of the decree issued after conquering of the two kingdoms.
During the early Middle-Acient (中古) period, Silla strove for the triangular position of the three kingdoms. Its intention was to recognize the coexistence of the three kingdoms, secure Silla's hegemony over the wars, and establish Silla's dominance in the relations among the three kingdoms. In 643, Silla shifted its war objective from the triangular position to the conquest of the two kingdoms. Therefore, Silla's wars to overthrow the two kingdoms had continuity.
This influenced the post-war handling of the War of Unification of the Three Kingdoms. In 668, Silla conducted heonburye offering prisoners to royal ancestral shrine and commemorating the fall of the two kingdoms. In 669, Silla promulgated the decrees notifying conquest of the two kingdoms and amnesty orders to prepare for the Silla-Tang War. The implication of the promulgation of the decree can be found in the fact that Silla's perception of the fall and conquest of the two kingdoms was transformed into a recognition of the unification of the Three Kingdoms.