The Kangxi Emperor, also known by his temple name Emperor Shengzu of Qing, personal name Xuanye, was the third emperor of the Qing dynasty, and the second Qing emperor to rule over China proper. His reign of 61 years makes him the longest-reigning emperor in Chinese history and one of the longest-reigning rulers in history. He is considered one of China's greatest emperors.

Throughout Chinese history, "Emperor" was the superlative title held by the monarchs who ruled various imperial dynasties. In traditional Chinese political theory, the emperor was the "Son of Heaven", an autocrat with the divine mandate right to rule all under Heaven. Emperors were worshiped posthumously under an imperial cult. The lineage of emperors descended from a paternal family line constituted a dynasty, and succession in most cases theoretically followed agnatic primogeniture.