Yang Yan was the daughter of Yang Wenzong, a marquess during Cao Wei, and his wife Lady Zhao. Her mother died early, probably when she was still in infancy, and she was initially raised by her maternal uncle and aunt—who breastfed her. After she grew older, she became raised by her stepmother Lady Duan; by this point, her father, who said to have died early as well, was probably dead. When she was young, she was described as intelligent, studious, and beautiful. A fortuneteller once foretold that she would have extraordinary honor, and it is said that when the Cao Wei regent Sima Zhao heard this, he took her and married her to his son Sima Yan. She bore for her husband three sons and three daughters. After Sima Zhao's death in 265, Sima Yan inherited his position and soon forced the Cao Wei emperor Cao Huan to abdicate in favor of him, ending Cao Wei and establishing Jin Dynasty. In 266, he created her empress.
As empress
Empress Yang's oldest son, Sima Gui, died in childhood, making her second son, Sima Zhong the legitimate heir, by traditional succession laws. However, Emperor Wu hesitated about selecting him as crown prince because he was developmentally disabled. Empress Yang was instrumental in persuading him to have her son designated crown prince anyway, arguing that tradition should not be abandoned easily. She was also instrumental in her son's selection of a wife, as Emperor Wu initially favored Wei Guan's daughter, but Empress Yang, friendly with Jia Chong's wife Lady Yang, praised Jia's daughter Jia Nanfeng greatly, leading to Jia Nanfeng's selection as crown princess. In 273, when Emperor Wu was undergoing a major selection of beautiful women to serve as his concubines, he initially put Empress Yang in charge of the selection process. She preferred those with slender bodies and fair skin, but did not favor those who have beautiful faces. She also left off a beauty named Bian, whom Emperor Wu favored—stating that since the Bians have served as empresses for three generations during Cao Wei that it would be too degrading for her to be a concubine. These caused Emperor Wu to be displeased, and he took over the selection process himself. Despite this and her husband's obsession with accumulating concubines, however, they appeared to continue to have genuine affection for each other. In 274, Empress Yang grew ill. She became concerned that whoever would be empress next—and she was particularly concerned about Consort Hu Fen, whom Emperor Wu greatly favored—would not support her son. She therefore asked Emperor Wu to marry her cousin Yang Zhi. Emperor Wu, distressed over her illness, agreed. She died soon thereafter and was buried with honors due an empress, at the tomb that her husband was eventually buried at when he died in 290. Concubine Zuo Fen wrote a long song of mourning in her honour. In 276, based on his promise to her, the emperor married Yang Zhi and created her empress.
