There are few reasonable evidences why “Sea of Japan” is incorrect wording. First of all, East sea have been called “East Sea” since 2000 years before which is even 700 years ahead compared to when the term “Japan” started to be used. Therefore, in historical point of view “East Sea” is way more justifiable wording compared to “Sea of Japan”. Since the East Sea region is a sea area adjacent to four countries including South Korea, North Korea, Japan, and Russia, it is not correct to name the sea area according to only one of the countries concerned, and it is necessary to find a name that all of the countries concerned can agree on. If this is not possible, it is appropriate to write the name used by the country concerned. The United Nations Conference on the Standardization of Geographical Names, which deals with the standardization of geographical names, also recommends that, in case of dispute over geographical names, it is recommended to be provisionally attached until an agreement is reached between the relevant countries. The general methodology for determining the geographical name of the ocean is customary to follow the name of the continent located to the left of the relevant sea area. In the case of the East Sea, we are insisting on the use of the East Sea as a sea located in the east of the Eurasian continent, not only as the Korean Peninsula.

For official web page, “Sea of Japan” is not the right wording to be used. The process of correcting may be laborious but the term “ Sea of Japan” is wording that deny the whole 2000 years history and it is also against the United Nations Conference on the Standardization of Geographical Names. These days many people gain knowledge from the Internet, so this minor issue in your website can be critical. I will be looking forward to your reply and further questions are welcomed.