Princess Taiping (Chinese: 太平公主; pinyin: Tàipíng Gōngzhǔ, lit. "Princess of Great Peace", personal name unknown, possibly Li Lingyue (李令月)) (died 2 August 713) was a royal princess during the Tang dynasty and her mother Wu Zetian's Zhou dynasty. She was the youngest daughter of Wu Zetian and Emperor Gaozong and was powerful during the reigns of her mother and her elder brothers Emperor Zhongzong and Emperor Ruizong (both of whom reigned twice), particularly during Emperor Ruizong's second reign, when for three years until her death, she was the real power behind the throne. As a princess, she was involved in political difficulties and developments during the reigns of her mother and brothers, especially during the reign of Emperor Ruizong, where she played a key and determinant role in the administration of the empire, Indeed, after the coup against Empress Dowager Wei, she became the real ruler behind the throne (following the example set by her mother and her brother's wife). Eventually, however, a rivalry developed between her and her nephew, Emperor Ruizong's crown prince Li Longji. After Emperor Ruizong yielded the throne to Li Longji (as Emperor Xuanzong) in 712, the conflict came to the political forefront; in 713, Emperor Xuanzong, according to historical records, believing that she was planning to overthrow him, acted first, executing a large number of her allies and forcing her to commit suicide.