t ▁K ha ▁and ▁D ư ơ ng ▁N h ị ▁K ha . ▁ ▁Sub ordinate ▁general ▁period ▁He ▁was ▁a ▁sub ordinate ▁general ▁of ▁Kh ú c ▁H ạ o ▁in ▁the ▁area ▁of ▁A ich au ▁( now ▁Th anh ▁H ó a ▁Province ). ▁In ▁the ▁year ▁ 9 3 1 , ▁D ư ơ ng ▁ Đ ì n h ▁N gh ệ ▁defeated ▁Ly ▁Kh ắ c ▁Ch ín h ▁and ▁Ly ▁Ti ế n , ▁took ▁up ▁the ▁capital ▁of ▁ Đ ạ i ▁La ▁( former ▁name ▁of ▁H ano i ), ▁prof essed ▁himself ▁as ▁" T i ế t ▁ đ ộ ▁s ứ " ▁( equ ivalent ▁to ▁Lord ▁Prote ctor ), ▁a ▁title ▁established ▁by ▁the ▁Chinese ▁government ▁to ▁rule ▁Gia o ▁Ch <0xE1> <0xBB> <0x89> , ▁a ▁district ▁that ▁covered ▁of ▁what ▁is ▁now ▁the ▁northern ▁area ▁of ▁Vietnam . ▁D ư ơ ng ▁Tam ▁K ha ▁became ▁a ▁sub ordinate ▁general ▁of ▁his ▁father . ▁ ▁Six ▁years ▁later , ▁Ki ề u ▁C ô ng ▁Ti ễ n , ▁also ▁a ▁general ▁of ▁D ư ơ ng ▁ Đ ì n h ▁N gh ệ , ▁mut in ied ▁and ▁killed ▁his ▁master ▁in ▁order ▁to ▁replace ▁D ư ơ ng ▁ Đ ì n h ▁N gh ệ ▁as ▁" T i ế t ▁ Đ ộ ▁S ứ ". ▁In ▁ 9 3 8 , ▁Ng ô ▁Qu y ề n , ▁son - in -