A shekara ta 854, sabon gwamnan Annan, Li Zhuo, ya haifar da gaba da rikici da kabilun tsaunuka, ta hanyar rage cinikin gishiri da kashe manyan sarakuna, wanda ya haifar da sauya sheka daga manyan shugabannin yankin zuwa masarautar Nanzhao.Basaraken yankin Lý Do Độc, dangin Đỗ, shugaban yaƙi Chu Đạo Cổ, da kuma wasu, sun sallama ko kuma sun haɗa kai da Nanzhao.^{[106 <]} > A cikin 858 sun kori babban birnin Annan.A cikin wannan shekarar ne kotun Tang ta mayar da martani inda ta nada Wang Shi a matsayin gwamnan soja na Annan, da nufin maido da zaman lafiya, da karfafa tsaron Songping.^[107] An tuna Wang Shi don magance tawayen Qiu Fu a Zhejiang a ƙarshen 860. Arewacin Vietnam daga nan ya koma cikin rudani da hargitsi.Sabon gwamnan sojan kasar Sin Li Hu, ya zartar da hukuncin kisa kan Đỗ Thủ Trừng, wani babban basarake na yankin, ta haka ya raba da yawa daga cikin manyan dangin Annan.^[108] Da farko mutanen garin sun maraba da sojojin Nanzhao, kuma sojojin hadin gwiwarsu sun kama Songping a watan Janairun 861, suka tilastawa Li Hu gudu.^[109] Tang ta yi nasarar kwace yankin a lokacin rani na 861. A cikin bazara na shekara ta 863 Nanzhao da 'yan tawaye sun kai 50,000 karkashin Janar Yang Sijin da Duan Qiuqian sun kaddamar da Siege na Songping.Birnin ya fadi a karshen watan Janairu yayin da sojojin kasar Sin suka janye daga arewa.^[110] An shafe Ma'ajin Annan.^[111]Tang ta kaddamar da farmaki a watan Satumba na shekara ta 864 karkashin Gao Pian, wani gogaggen Janar wanda ya yi yaki da Turkawa da Tanguts a arewa.A cikin hunturu 865-866, Gao Pian ya sake kwace Songping da arewacin Vietnam, kuma ya kori Nanzhao daga yankin.^[112] Gao ya hukunta mutanen yankin da suka yi kawance da Nanzhao, ya kashe Chu Đạo Cổ da 30,000 'yan tawayen gida.^{[113 <]} > A shekara ta 868 ya canza sunan yankin zuwa "The Peaceful Sea Army" (Jinghai guan).Ya sake gina kagara Sin Songping, ya sa masa suna Đại La, ya gyara katangar birni mai tsawon mita 5,000 da ta lalace kuma ya sake gina matsuguni 400,000 ga mazaunanta.^{[112 <]} > An girmama shi sosai har ma daga baya Vietnamese.^[114]