In ancient Korean history, there was a king who had a large influence on China and Japan. It was King Geunchogo, the thirteenth king of Baekje, who used the ocean to expand its economic and cultural influence across the region. Several Chinese and Japanese history books describe how Baekje influenced their kingdoms with its naval forces and advanced navigation during King Geunchogo’s reign. For example, the Book of Song, written in 488 by Chinese historian Shen Yue, wrote, “Baekje conquered and ruled China’s Liaoxi region and named it Jinping-jun Jinping-xian.”
There are also Japanese records that state that the Seven-Branched Sword, Japan’s national treasure, was a gift from Baekje and that the Japanese king was marveled by its exquisite craftmanship. This 75cm-long iron sword with seven branch-like prongs shows Baekje’s masterful metal craftsmanship. King Geunchogo achieved Baekje’s cultural and economic prosperity and expanded its influence to China’s Liaoxi and Shandong regions and to Japan by venturing across the ocean and building diplomatic relationships. King Geunchogo was an adventurous king, who established sea routes to connect the continent to the ocean and left lasting legacies across China and Japan.