Battle of Unju (934) — the same event in Goryeosa and Goryeosa Jeolyo

Goryeosa: Taejo personally conquers Unju and fights Gyeon Hwon, defeating him badly; more than thirty castles north of Ungjin submit just on hearing…

What each source says

Goryeosa (History of Goryeo) · AD 934 · 홍성

Taejo personally conquers Unju and fights Gyeon Hwon, defeating him badly; more than thirty castles north of Ungjin submit just on hearing of him.

九月丁巳,自將征運州,與甄萱戰,大敗之,熊津以北三十餘城,聞風自降。
Location: 世家 卷2 太祖 十七年

Goryeosa Jeolyo (Essentials of Goryeo History) · AD 934 · 洪城

The king personally campaigns against Unju; Gyeon Hwon sends 5,000 armored troops to sue for peace, but Yu Geum-pil charges with cavalry and kills over 3,000, and more than 30 fortresses north of Ungjin surrender

」及彼未陣,以勁騎數千突擊之,斬獲三千餘級,擒術士宗訓醫師訓謙勇將尙達崔弼,熊津以北三十餘城,聞風自降。
Location: 권1 太祖神聖大王 十七年

Place: 홍성

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