After Gaozong's death, Empress Wu as empress dowager and regent conquered power completely and sole, and seven years later, she seized the throne in the Zhou dynasty, becoming the only empress regnant in Chinese history. Wu was granted certain honors and privileges which were not enjoyed by any Chinese empresses before or after. In the last years of his reign, Emperor Gaozong was unable to run the state due to illness, so he delegated his responsibilities to Empress Wu. Gaozong sought her views on all matters before issuing orders. She was given charge of the Heirloom Seal of the Realm, implying that her perusal and consent were necessary before any document or order received legal validity. She was wholly present when the Emperor held court, and even held court independently when the Emperor was unwell. She set up spies to build a strong intelligence system in the court and throughout the empire to deliver daily reports on current affairs of the empire or opposition to the central state. She was more decisive and proactive than her husband, and she is considered by historians to have been the real power behind the throne for more than eighteen years and she supervised the court and the performance of officials and officers on a daily basis. A strong, charismatic, cunning, vengeful, ambitious and well-educated woman who enjoyed the absolute interest of her husband, Wu was the most powerful and influential woman at court during a period when the Tang Empire was at the peak of its glory. After her wedding to Gaozong in 655, Empress Wu's rise to power was swift.
Īfter re-entering the Emperor Gaozong's harem, she clashed with Empress Wang and Consort Xiao to gain the emperor's affection, and eventually expelled and killed them. After Gaozong's debilitating stroke in 660, Wu Zetian became administrator of the court, a position equal to the emperor's, until 705.
After his death, she married his successor-his ninth son, Emperor Gaozong, officially becoming Gaozong's huanghou ( 皇后), or empress consort, in 655, although having considerable political power prior to this. Under her 40-year reign, China grew larger, corruption in the court was reduced, its culture and economy were revitalized, and it was recognized as one of the great powers of the world. She was the only legitimate female sovereign in the history of China. She subsequently became empress regnant of the Wu Zhou dynasty of China, ruling from 690 to 705. Wu Zhao, commonly known as Wu Zetian (17 February 624 – 26 November 705), alternatively Wu Hou, and during the later Tang dynasty as Tian Hou, was the de facto ruler of the Tang dynasty, first through her husband the Emperor Gaozong and then through her sons the Emperors Zhongzong and Ruizong, from 665 to 690.