Although, until the Three Kingdoms Period, mainly the coastal sea roads had been relied on, ever since the Unified Silla(新羅), the sea roads that cross or divide the Yellow Sea had been newly pioneered. With the sea roads getting diversified and expanded, the civilization interchanges in East Asia had been developing innovatively. Such a trend had continued until the Koryo(高麗) Dynasty.
However, entering into the 13^th century, while being invaded by the Mongol Empire, a new situation was entered into. The mighty sea power of Koryo fell. And the island and coastal regions continued to be desolated.
At the end of the Koryo Dynasty, although the discussions about reconstructing the island and coastal regions took place, the newly-born Joseon(朝鮮) could not accept this. For Joseon, there was no choice but to follow up the measures of the sea prohibition and the empty islands of Ming(明).
From the latter half of the 17^th century, the islands changed from a space in which one cannot live to a space in which one can live. But the sea prohibition became even more strengthened. Such a situation had continued until concluding the terms between Josun and Japan in 1876.

Ⅰ. 머리말
Ⅱ. 해양활동의 성장 · 번영기 : 고대~고려시대
Ⅲ. 해양활동의 소강기 : 조선시대
Ⅳ. 맺음말
참고문헌
Abstract