The Sea of Japan (or the Japan Sea) is a sea area located along the northeastern part of the Asian continent. It is separated from the North Pacific Ocean by the Japanese Archipelago and Sakhalin.

Historically, the name“Sea of Japan” was first established in Europe from the late 18th century to the early 19th century,and has been used for more than 200 years. When seas are separated from oceans, they have been frequently named after major archipelagos or peninsulas that separate them. The name“Sea of Japan" focuses on one key geographical feature - the Japanese Archipelago that separates this sea area from the Northern Pacific Ocean.

In fact, without the presence of the Japanese Archipelago, this sea area would not exist.

Because of this obvious geographical characteristic, the name “Sea of Japan” came to be widely accepted throughout the world. At present, more than 97% of the maps used around the world, except for those in the Republic of Korea (ROK) and North Korea, use only the name “Sea of Japan". This name has been internationally established.

Despite this global recognition, ROK and North Korea suddenly proposed that the name “Sea of Japan” should be changed at the sixth United Nations Conference on the Standardization of Geographical Names in 1992. They continue to raise this issue at related international conferences of the United Nations and at meetings of the International Hydrographic Organization (IHO).

They argue that the name “Sea of Japan” became widely used from the beginning of the 20th century, as a result of Japan's expansionism and colonialism. For this reason, they maintain that the name should be changed to the “East Sea," as ROK and North Korea domestically use,or at least, that both the “East Sea” and the “Sea of Japan” should be used together. However, the assertion made by ROK and North Korea is unfounded, and there is neither reasoning nor merit behind the call for such a change.