'Donghae' is a name that Koreans have been using for more than 2,000 years, and it is mentioned in t "Samguksagi (ß²ÏÐÞÈÑÀ)" edition of King Dongmyeong, the tombstone of Gwanggaeto the Great, "Eight Islands Chongdo (ø¢Ô³õÅÓñ)", and "Aguk Chongdo (ä²ÏÐõÅÓñ)" This fact can be confirmed in various sources and old maps.
On the other hand, it is claimed that the name 'Sea of Japan' was first used in "The Map of All Nations" by Matteo Ricci in 1602. However, various historical documents prove that the Japanese themselves did not recognize the name of the East Sea area as the ¡°Sea of Japan¡±. In particular, Japan presents the results of a survey on Western ancient maps showing that the use of the 'Sea of Japan' increased in the 19th century and claims that the name of the 'Sea of Japan' was established in the 19th century, but according to the Japanese maps Byeongyeokdo (ìíÜâÜ«Í£ÕÔÓñ, 1809) and Shinjeyeojijeondo (ãæð²æ«ò¢îïÓñ, 1844), you can see that it is marked as the East Sea.