The Shilla kingdom and the Tang Empire remained close for much of the Unified Shilla Period. Like many other East Asian kingdoms, Shilla paid tribute to the Tang Emperor and routinely dispatched envoys to the Tang capital in order to maintain valuable diplomatic and trade relations. Shilla aristocrats were great admirers of the advanced technological and administrative innovations of their enormous neighbor and thus were zealous in facilitating the importation of Tang court dress, titles, literary styles, writing, arts, philosophies and administrative methodologies.
This is not to say that the Shilla administration modeled itself after Tang completely, however. As in its earlier history, while Tang culture and political ideas entered Shilla, cultural imports were localized to suit the local situation and Shilla civilization continued to maintain a relative distinctness. Unlike the Tang Empire, Shilla was a Buddhist kingdom with Buddhism as the state religion and it enjoyed official sanctioning; Shilla rulers at times regarded themselves as virtual Buddha-kings. Shilla's administrative divisions followed that of the ancient Zhou Dynasty instead of the Tang and also featured a particularly powerful aristocracy that had much control over the monarchy, whereas the political powers of aristocrats in comparison to that of the central authority the Tang court were on the decline. While the Tang moved towards a trend of increased centralization and the strengthening of the power of the emperor, the traditional aristocracy of Shilla monopolized the royal court.
Sources:
Seth, Michael J. A Concise History of Korea. Rowman & Littlefield Publishers, Inc. 2006









