Chang'an (581) — the same event in Book of Sui and Book of Zhou

Book of Sui: Yang Jian ascended the throne in the Linguang Hall, built an altar in the southern suburbs to report to Heaven, and adopted the era name…

What each source says

Book of Sui (Suishu), Imperial Annals · AD 581 · 長安

Yang Jian ascended the throne in the Linguang Hall, built an altar in the southern suburbs to report to Heaven, and adopted the era name Kaihuang. The Sui dynasty was founded.

備禮即皇帝位於臨光殿
Location: 隋書 卷001 帝紀 大定1年2月

Book of Zhou (Zhoushu), Imperial Annals · AD 581 · 長安

Yang Jian, Prince of Sui, takes a royal title (founding the Sui); Emperor Jing retreats to a separate palace, ending Northern Zhou at age 33. The Sui enfeoffs Emperor Jing as Duke of Jie

甲子,隨王楊堅稱尊號,帝遜于別宮。
Location: 周書 卷8 大定1年2月

Place: 長安

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