The concise content of 李白’s ‘writing a reply to a foreign country(草答蕃書)’ was transmitted to various literature, and then it was embodied as a concrete event in the late Ming(明末) novel <lǐ-zhé-xiān-zuì-cǎo-xià-mán-shū (李謫仙醉草嚇蠻書)>(included in the 『警世通言』 and 『今古奇觀』 as well). I found out that such a detail as a novel was already made in Luo Guan-zhong(羅貫中)’s novel 『suí-táng-liǎng-cháo-shǐ-chuán(隋唐兩朝史傳)』, and that <李謫仙醉草嚇蠻書> changed the foreign country from Kitan(契丹) to Balhae(渤海), accepting its contents. In this novel, when an envoy of 渤海 delivers a national letter written in its own language and demands that territory taken over by Tang(唐), 李白 frustrates the request by writing a reply, ‘hyek-man-seo(嚇蠻書)’ in 渤海’s letter also. Why did <李謫仙醉草嚇蠻書> set the other country in 渤海? In this novel, 渤海 asked for the old land of Goguryeo(高句麗), and when the 渤海’s envoy came, the officials of 唐 dynasty reminded of the hardships & frustrations that Taejong(太宗) suffered during the war with 高句麗. And in his ‘嚇蠻書’, 李白 warned that 渤海 would eventually follow the train of 高句麗, which had been destroyed by 唐. The intention of this novel is to resolve the complex of China that was caused by the failure of several times in the war with 高句麗 through the fictional history which made 渤海, a country that succeeded 高句麗 and existed at the time of 李白, appear. Several Korean scholars including Shin Chae-ho(申采浩) have regarded the contents of <李謫仙醉草嚇蠻書> as true, and have mentioned that 渤海 was an independent and strong nation based on the fact that 渤海 had diplomacy with 唐 in its own language. However, because 渤海 and 唐 maintained a friendly relationship in the period when the story unfolds, the contents that 渤海 threatened 唐 by a national letter were not realistic, and unlike the viewpoints of scholars in the past, this is the story that 渤海 finally surrendered to 唐 and paid tribute. Rather, it is more important to know that the Chinese works themselves reflect the consciousness of close connection or succession between 高句麗·渤海 and the perception of the fact that 高句麗 competed fiercely with 唐 as an independent country. This is because it is not only true to the reality of the work, but it will also help to establish the right recognition of ancient history between Korea and China.