Who was  the last emperor or last "Son of Heaven" of China?
Emperor of China The Emperor of China () was the sovereign of Imperial China reigning between the founding of the Qin dynasty that unified China in 221 BC, until the abdication of Puyi in 1912 following the Xinhai Revolution and the establishment of the Republic of China. The emperor was also referred to as the "Son of Heaven" (), a title that predates the Qin unification and recognized as the ruler of "all under heaven" (i.e., the whole world). In practice not every Emperor held supreme power in China, although this was usually the case.
Emperor Renzong of Song Emperor Renzong of Song (30 May 1010 – 30 April 1063, Chinese calendar: 14 April 1010（the 3rd year of Dazhongxiangfu, 大中祥符三年） - 29 March 1063 (the 8th year of Jiayou, 嘉祐八年)), personal name Zhao Zhen, was the fourth emperor of the Song dynasty in China. He reigned for about 41 years from 1022 to his death in 1063, and was the longest reigning Song dynasty emperor. He was the sixth son of his predecessor, Emperor Zhenzong, and was succeeded by his cousin's son, Emperor Yingzong, because his own sons died prematurely. His original personal name was Zhao Shouyi but it was changed by imperial decree in 1018 to "Zhao Zhen", which means 'auspicious' in Chinese.