In the Ancient Korean history, Shinmiguk(新彌國), one of the territorial state, was the most powerful and prosperous. It located in the west-south coast line in the Korean Peninsular so that this state could control in this coast line. But this state declined during the fourth century because of declining its trade with stronger neighboring states such as Narkrang and Daebang. As declining of Shinmiguk, a new power appeared in that section. They were the powerful marine powers located coast line in Shinwallri(신월리) of Bukil(북일). They had a commanding site called Shiwallri Toseong(신월리토성) and Seongmasanseong(성마산성) to control in these coast section such as Kangin(康津), Haenam(海南), Wando(완도). On the while, After Shimiguk, other powers appeared in the Youngsan River(榮山江). They were Youngam(영암)'s people. From the early and middle of four century to the middle of five, they controled in this section. We could know their power through their monuments and sites such as Seungtlebongtoseong(성틀봉토성) and its neighboring tombs, Okyari(옥야리) and Shinyeonri(신연리) tombs. By the middle of five century, the dominant power in the Younsan River had been changed into Banam(반남) people. They could control all these section through utilizing not only agricultural and fishing dominant power but also obtaining intermediary trade power between native powers in there. Now, we could also tmderstand their power through such monuments and tombs as Jaminsanseoung(자미산성), Daeanrii tombs(대안리고분군), Shinchonrii tombs(신촌리고분군), Deurksanri tombs(덕산리고분군). There were also many difference monuments, tombs and walls in the Chennam province(全南城万). And so , I suppose that there were many states in these section.