The Sea of Japan is a body of water to the west of Japan. It is bounded by Japan, the Russian island of Sakhalin, the far-eastern coast of Russia, and Korea. It is connected by the Korea Strait (or Tsushima Strait) to the East China Sea.
Russian admiral Krusenstern made popular the "Sea of Japan" (Japonskoe More) name in the West through the publication of his memoir in 1815.