According to Empress Dowager Xiao's biography in the Old Book of Tang, she died in the middle of Emperor Wuzong's Huichang era (841–846), but that contradicted the other accounts about her death, which indicated that her death was in 847, during the reign of Emperor Xuānzong. Further confusing the situation was the date of her death in 847. Her biography in the New Book of Tang indicated that she died in 847 but did not give a date. The chronicle of Emperor Xuānzong's reign in the Old Book of Tang gave her death as being in the fourth month of the lunar calendar but did not give a day. The Zizhi Tongjian gave her death as being on the Jiyou day of the third month of 847, which did not exist in the sexagenary cycle for dating. The chronicle of Emperor Xuānzong's reign in the New Book of Tang, which indicated "the Empress Dowager" died on the Jiyou day of the fourth month of 847 but did not specify which empress dowager it was (although it indicated later, at the time of her burial, that it was "Empress Dowager Zhenxian" (i.e., Empress Dowager Xiao)), the only major traditional account that gave an actual date of her death, is thus used here. Compare Old Book of Tang, vols. 18, part 2 [chronicle of Emperor Xuānzong's reign], 52 [biographies of empresses], New Book of Tang, vols. 8 [chronicle of Emperor Xuānzong's reign], 77 [biographies of empresses], and Zizhi Tongjian, vol. 248.
As Li You was the Prince of Jian'an only from 805 to 806, her beginning to be his concubine must be at that time. See Old Book of Tang, vol. 16.
