Luoyang (684) — the same event in Old Book of Tang and Zizhi Tongjian

Old Book of Tang: Wu Zetian deposed Emperor Li Xian, made him Prince of Luling, and confined him separately.; Zizhi Tongjian: In February 684 (Wuwu…

What each source says

Old Book of Tang (Jiu Tangshu), Annals · AD 684 · 洛陽

Wu Zetian deposed Emperor Li Xian, made him Prince of Luling, and confined him separately.

二月戊午,廢皇帝為廬陵王,幽於別所,仍改賜名哲。
Location: 舊唐書 卷6 嗣聖1年 2月

Zizhi Tongjian (Comprehensive Mirror) · AD 684 · 洛陽

In February 684 (Wuwu day), the Empress Dowager gathers the officials at Qianyuan Hall; Pei Yan and others enter the palace with troops, proclaim the Empress Dowager's order, depose Emperor Zhongzong as Prince of Luling, and lead him down from the hall.

二月,戊午,太后集百官於乾元殿,裴炎與中書侍郎劉禕之、羽林將軍程務挺、張虔勖勒兵入宮,宣太后令,廢中宗為廬陵王,扶下殿。
Location: 권203 684년 항

Place: 洛陽

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