Empress Dowager Guo (郭太后, personal name unknown) (died June 25, 848), formally Empress Yi'an (懿安皇后, "the benevolent and peaceful empress"), was an empress dowager of the Chinese Tang dynasty. During the reign of her husband Emperor Xianzong, she was commonly regarded as his wife and the proper empress even though she never received the title from him, and she subsequently served as empress dowager during the reign of their son Emperor Muzong, their grandsons Emperor Jingzong, Emperor Wenzong, Emperor Wuzong, and his son (by a concubine) Emperor Xuānzong.
Background
It is not known exactly when the future Empress Dowager Guo was born. Her father was the official Guo Ai (郭曖), one of the sons of the great general Guo Ziyi, and her mother was Princess Shengping, a daughter of Emperor Daizong. In 793—by which time her father Guo Ai was described to be deceased—she married Li Chun the Prince of Guangling, the oldest son of Li Song the Crown Prince, son of then-reigning Emperor Dezong (Emperor Daizong's son). (She was therefore marrying her cousin's son.) She thus became the Princess of Guangling. It was said that because her mother was a princess and her grandfather and father both had great contributions to the state, she was much favored by her father-in-law Li Song. In 795, she gave birth to Li Chun's third son Li You. Later she gave birth to Li Chun's sixth son Li Wu and a daughter Princess Qiyang.
As imperial consort
In 805, Emperor Dezong died, and Li Song became emperor (as Emperor Shunzong), but as Emperor Shunzong was seriously ill himself, he yielded the throne to Li Chun later that year, and Li Chun took the throne (as Emperor Xianzong). Shortly after Emperor Xianzong took the throne, Princess Guo's mother Princess Shengping offered a tribute of 50 women to Emperor Xianzong, but Emperor Xianzong declined on the rationale that if Emperor Shunzong was not accepting tributes, neither could he. In 806, Emperor Xianzong created Princess Guo Guifei (貴妃) — the highest rank for imperial consorts — but did not create her empress, Because the position of empress was empty, even the central palace (residence of empresses) was given to her for living, and he left the administration of the palaces to her, and in all the special ceremonies of the imperial palace, court or family, she was allowed to sit in the same seat that only the empress could sit next to the emperor, the salary and daily necessities of her life in the palace were equal to the magnificent luxuries of an empress. He also did not create Li You crown prince; rather, he only created Li You the Prince of Sui, instead creating Li You's older brother Li Ning, the son of his concubine Consort Ji, crown prince. Only after Li Ning died in 811 was Li You (who was renamed Li Heng) created crown prince, bypassing another older brother, Li Kuan (李寬) the Prince of Li. Before doing so, Emperor Xianzong had the imperial scholar Cui Qun draft a petition offering to yield on Li Kuan's behalf, but Cui pointed out that Li Heng was born of a wife — and in doing so, recognized Consort Guo as Emperor Xianzong's wife rather than concubine — whereas Li Kuan was born of a concubine, and argued that such a petition would be unnecessary. Emperor Xianzong agreed and did not insist on such a petition.
It was said that the officials, throughout the years, submitted repeated petitions that Consort Guo be created empress, and the efforts became particularly intense in 813. However, Emperor Xianzong, who had many favorite concubines, was concerned that due to Consort Guo's honored lineage, if he created her empress, the other concubines would not be able to have sexual relations with him. He therefore declined on the basis that the times were not fortunate times.
In 820, Emperor Xianzong died suddenly — a death that was commonly believed to have been a murder carried out by the eunuch Chen Hongzhi (陳弘志). After some confusion, in which the powerful eunuch Tutu Chengcui apparently tried to have Li Kuan (whose name had been changed to Li Yun (李惲) by this point) made emperor, several other key eunuchs — Liang Shouqian (梁守謙), Ma Jintan (馬進潭), Liu Chengjie (劉承偕), Wei Yuansu (韋元素), and Wang Shoucheng — had Tutu and Li Yun killed, and they supported Li Heng to be emperor (as Emperor Muzong). Emperor Muzong honored Consort Guo as empress dowager. (Another son of Emperor Xianzong's, Li Yi, would later suspect Consort Guo and Li Heng of being complicit in Emperor Xianzong's murder, although there was no particular evidence linking either to the murder.)