Wu Chao (also Wu Hou or Wu Zetien) was born into a noble Chinese family and began serving the emperor as a concubine when she was a young teenager. As the mother of two of the emperor's sons, Wu gained power in the palace. Although little about her was written during her life, the story goes that Wu successfully accused the empress of murder, then took her place. After a few years of marriage, the emperor became incapacitated and Wu took over. After he died, she manipulated her sons so that she was the de facto ruler, and in 690 she was declared Empress. Under her reign, the Tang dynasty continued to unify and Wu helped to encourage the growth of Buddhism in China.