Grand empress dowager (also grand dowager empress or grand empress mother) (Chinese and Japanese: 太皇太后; pinyin: tàihuángtàihòu; rōmaji: taikōtaigō; Korean: 태황태후 (太皇太后); romaja: Tae Hwang Tae Hu; Vietnamese: Thái Hoàng thái hậu) was a title given to the grandmother, or a woman from the same generation, of a Chinese, Japanese and Korean emperor in East Asia, or a Vietnamese emperor in Southeast Asia.
Some grand empress dowagers held regency during the emperor's childhood. Some of the most prominent empress dowagers extended their regencies beyond the time when the emperor was old enough to govern alone. This was seen as a source of political turmoil, according to the traditional views of Chinese historians.
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