Wu Zetian was born around 624 as the daughter of Wu Shihuo, Duke Ding of Ying and Lady Yang. She was born into a rich family with connections to the ruling dynasty, and because of this, she was also rather well-educated. When she was 14 years old, she was taken to be an imperial concubine of Emperor Taizong of Tang, and she was given the title of cairen, which ranked as fifth in the Tang’s nine-rank system for imperial officials, nobles and consorts.
Emperor Taizong died in 649 and was succeeded by his son, Emperor Gaozong of Tang. As Wu did not have any children with the deceased Emperor, it was customary that she was to be confined to a monastic institution, and she was consigned to the Ganye Temple. However, she was brought back as a concubine by the new Emperor, who knew her from during his father’s lifetime.
By the early 650s, she had risen to the title of Zhaoyi, which was the highest ranking of the nine concubines of the second rank. In 652, she gave birth to her first son, and in 653, she gave birth to a second son. In 654, she gave birth to a daughter, who died not much later. Empress Wang was removed from her position as Empress. Wu was created Empress in her place. Empress Wang was eventually executed.
In 655, Wu officially became the new Empress Consort, and her son was designated as crown prince. By 657, Empress Wu began avenging herself against all those who had opposed her accension. Several were executed and exiled. Even the former crown prince was placed under house arrest.
By 664, Empress Wu had so much power that it began to anger Emperor Gaozong. It was suggested to him that he depose her, and the edict was drawn up. Wu pleaded her case with the Emperor, and she managed to persuade him.
As Emperor Gaozong’s health began to decline, he considered having Empress Wu rule as regent. This never formally happened, but when he died in 683, the throne was taken by their son, now Emperor Zhongzong. However, she retained power as Empress Dowager. Emperor Zhongzong reigned for just six weeks, as his mother had him deposed, and she made her youngest son Emperor Ruizong. It was Wu who held power now.
By 690, Wu was set to become Empress Regnant of the newly proclaimed Zhou dynasty, despite the fact that women were barred from the throne. She took the throne later that year and immediately faced the issue of succession. She created the former Emperor Ruizong crown prince. Just three years later, the Crown Princess was accused of using witchcraft, and she was executed. Ruizong did not dare to speak of her for fear of being next.
Wu reigned until her death on 16 December 705. 1
Empress Wu never murdered her daughter. That was slander. Jonathan Clements even stated that Empress Wu would never harmed her own child. Historians agreed that she did not. This rumor was written one hundred years after her death. Daughter of Heaven is not a good source of information. For a more balanced and true biography of Empress Wu, I recommend N. H. Rothschild.