According to the analyses of classic historical texts such as the 'Samguk Sagi' and 'Samguk Yusa', and also other inscription materials, the Silla dynasty, since its early days, had continued to employ protocols and procedures that were only meant for the Lord state. Such employment occurred in the dynasty's official functions in order to demonstrate the King's own ruling authority. But during those days, diplomatic negotiations with the outer world were not that frequent, and the people did not have much of a clear idea of exactly what place the Silla dynasty was occupying inside the international order at the time.
Coming into the middle period(中古期), Silla dynasty's direct contacts with the Chinese dynasties were increased, and as they had become aware of the Chinese dynasties'power, they decided to assume the position of a vassal in their dealings with the Chinese. Yet, inside their domain, they used not only the protocols and practices of the vassal states but also those of the lord state, and treated the Japanese people as a culturally inferior entity, and also as a threat present at the border area.
During the reigns of Queen Jindeok(眞德) and King Muyeol(武烈), the Silla people actively embraced the culture of the Chinese Tang dynasty, and also accepted the concept of their own relationship with the Chinese dynasties, which was a Tributary-Assignment relationship, with the Chinese dynasties at the most superior position. But, during the reign of King Munmu(文武), there had also been efforts to maintain a certain level of political independence in the wake of the ongoing Tang-Silla war, even when they were still in a relationship which was comprised of tributary actions, and assignments from higher beings. In the meantime, Silla dynasty's relationship with Japan was also affected by the tensions between Silla and Tang, and Silla agreed with the Japanese to establish a diplomatic relationship that Japan has favored, in which Silla agreed to assume the status of a vassal, until the late 7th. century and early 8th. century. Such agreement was considered only effective when the Silla emissaries were visiting Japan.
The early 8th. century was a turning point for the people of the Unified Silla dynasty. And it was also the time when the people's perception of the world or the universe, based upon the belief that Silla was at the center of such world or universe, was rekindled. Yet, from time to time, they had to accept the position of an inferior vassal state that was usually expected to pay tributes to the lord state, when they were confronting the Tang dynasty. Such condition required the Silla people to theorize that there was also a certain plural nature in the world.
It should also be noted that the Silla people's own claim of themselves being the Wangseong-guk(王城國, the Dominant Holy State), was a concept expanded from the Buddhist perception of the universe established during the reign of Queen Seondeok(善德). The people of the Unified Silla dynasty perceived the status of the East Asian society as a realm which contained a certain hierarchy, with Tang at the top, then Silla at the middle, and Parhae(渤海) and Japan at the bottom.