The Name “Sea of Japan” Is the Only Internationally Established Name(The Debate Concerning the Naming of the Sea of Japan - Analysis of the South Korean
Government’s Arguments based on Historical Materials and Maps-)
Masao Shimojo
Professor, Takushoku University
1. Introduction
Disagreement about the name of the Sea of Japan has persisted between Japan andSouth Korea since the sixth UN Conference on the Standardization of GeographicalNames (UNCSGN) in 1992. During this time, the Japanese government has consistentlymaintained that the name “Sea of Japan” is the only internationally established name,
The name “East Sea,” which the government of South Korea has insisted on using
instead of “Sea of Japan,” has historically referred to only the coastal waters off theKorean Peninsula, not the whole area of the Sea of Japan, and it does not qualify as analternative to the name “Sea of Japan.”
However, Seoul continues to object to the use of “Sea of Japan” and insist on “EastSea.” This is because the South Korean government, which has occupied the Japanese
territory of Takeshima (Korean name: Dokdo) since 1954, has associated this territorial
issue with the naming of the Sea of Japan. The issue has been taken up diplomaticallyby the South Korean government.
Part of the South Korean logic for justifying the name “East Sea” is that, if Dokdo(Takeshima) is in the Sea of Japan, then it inappropriately appears as if Dokdo is inJapanese territorial waters. In this regard, the South Korean government has claimed
that “East Sea” has been used for 2000 years and should be used instead of “Sea ofJapan.”
The basis for the claim that “East Sea” has been used for 2000 years is the phrase“beaches of the East Sea” from the Book of the Sage King Tongmyŏng of the Koguryŏ 1Annals (高句麗本紀始祖東明聖王条) in the Samguk sagi (三国史記, History of theThree Kingdoms). The South Korean side also argues that “East Sea” was excluded
from the International Hydrographic Organization’s 1929 Limits of Oceans and Seas, inKoguryŏ is one of the three kingdoms whose historical record is compiled in theSamguk sagi. It was established in the area north to the Yalu River in the 1st Century
BC and expanded its territory to parts of both the Korean Peninsula and northeastChina.
1spite of the name’s use for 2000 years before that, because Korea was under Japaneserule at that time and thus deprived of the opportunity to assert the legitimacy of thename “East Sea.”
Probably because of a belief that it would be difficult to reach an agreement on using
only “East Sea,” Seoul has argued since the 1997 conference of the International
Hydrographic Organization that both “Sea of Japan” and “East Sea” should be usedsimultaneously.
However, as discussed in detail below, the word 東海 (Donghae, Dong means Eastand Hae means Sea) that appears in the Samguk sagi, the Kwanggaet’o Stele (広開土王碑,a stone monument erected in 414), the P’alto ch’ongdo (八道総図, complete map ofthe eight provinces), the Aguk ch’ongdo (我国総図, complete map of Korea), and otherpieces of evidence 2 that have been identified by the South Korean government do notrefer to the Sea of Japan. The word 東海 (Donghae) appearing in these pieces only
refers to the eastern coastal waters off the Korean peninsula (not the whole Sea ofJapan) or the Yellow Sea or the East China Sea and has nothing to do with the body ofwater called the Sea of Japan today.
2. “East Sea” in the Aguk ch’ongdo
For example, it is true that the Aguk ch’ongdo mentions the Donghae (East Sea) tothe east of the Korean peninsula, but the western and southern coastal waters off theKorean peninsula are also indicated as Seohae (西海, West Sea) and Namhae (南海,South Sea), respectively. Seohae is a part of the Yellow Sea and Namhae is a part of theEast China Sea, so they are names for stretches of the Korean peninsula’s coastal waters.
In light of the South Korean government’s argument that “East Sea” should be usedinstead of “Sea of Japan,” it would also be natural for Seoul to claim that “Yellow Sea”
and “East China Sea” should be replaced with “West Sea” and “South Sea” respectively,
but Seoul is making no such demands. The only reason why the South Korean
government takes issue with the Sea of Japan is that is where Takeshima (Dokdo) islocated.

For the views of the South Korean Ministry of Foreign Affairs, see
http://www.mofa.go.kr/www/wpge/m_3838/contents.do2

Aguk ch’ongdo (我国総図, complete map of Korea)
In the Aguk ch’ongdo, in addition to “Donghae (東海, East Sea)” to the east of theKorean peninsula, the western and southern coastal waters off the Korean peninsula are
indicated as “Seohae (西海, West Sea)” and “Namhae (南海, South Sea),” respectively.
In light of the logic by the South Korean government, it should have taken issue with
Seohae and Namhae, too. But it has not done so.
Moreover, the fact that the East Sea in the Aguk ch’ongdo refers to only the stretchesof water off the eastern coast of the Korean peninsula can be verified by the Map of Liaodongand Korea (遼東連朝鮮図) in the Haifang zuanyao (海防纂要, Compilation on Maritime

Defenses), compiled by Wang Zaijin of the Ming. There, the western coastal waters off theKorean peninsula are indicated to be the Korean West Sea (朝鮮西海), the southern coastal
waters the Korean South Sea (朝鮮南海), and the eastern coastal waters the Korean East Sea(朝鮮東海.) They only mean the coastal waters off the Korean peninsula. Thus, the South
Korean government’s claims that “East Sea” in the Aguk ch’ongdo refers to the whole area of
the Sea of Japan are nothing other than an arbitrary interpretation of the map.

The Map of Liaodong and Korea (遼東連朝鮮図) in the Haifang zuanyao(海防纂要, Compilation on Maritime Defenses)

3. The “Beaches of the East Sea” from the Samguk sagi
We can see another example of the South Korean government’s arbitrary
interpretation of literature in its claims regarding the phrase “beaches of the East Sea”
from Koguryŏ Annals of the Samguk sagi, which is taken as evidence that “East Sea”
has been used for 2,000 years. The South Korean government does not doubt that
Koguryŏ is a part of Korean history, but China perceives Koguryŏ to be a regional
Chinese kingdom. From the perspective of the Chinese, “East Sea” in the phrase“beaches of the East Sea” refers to the Yellow Sea or the East China Sea.
Now, where were the “beaches of the East Sea” located? In the Samguk sagi, thephrase “beaches of the East Sea” was used to refer to the area where the Sage King
Tongmyŏng, the founder of Koguryŏ, moved to establish his new state. If so, we shouldbe able to infer where the East Sea was based on the territory of Koguryŏ at the time ofits founding. Looking at information about Koguryŏ in books such as the “Treatise on
Geography (地理志)” in the Hanshu (漢書, Book of Han), the “Treatise on Geography”
in the Hou Hanshu (後漢書, Book of the Later Han,) and the “Records of Wei: AnAccount of the Easterners (魏志東夷伝)” in the Sanguozhi (三国志, Records of theThree Kingdoms), 3 Koguryŏ was founded near the upper reaches of the Yalu River inthe 1st Century BC. The area to the east of Koguryŏ was occupied by Eastern Okchŏ (東沃沮). In other words, at the time of its founding, Koguryŏ’s territory was not adjacent to the Seaof Japan.

In fact, according to the Koguryŏ Annals of the Samguk sagi, Koguryŏ did not defeat
Eastern Okchŏ, expand its territory eastward, and reach the Sea of Japan until the reignof King T’aejo(太祖), the sixth ruler after the Sage King Tongmyŏng. 4 The “East Sea”
in the Samguk sagi, based on which the South Korean government asserts that the name“East Sea” has been in use since 2,000 years ago, was not the Sea of Japan.

According to “an Account of Koguryŏ” of the “Records of Wei: An Account of theEasterners” in the Sanguozhi, and “An Account of the Easterners” in the Hou Hanshu,“Koguryŏ lies to the east of Liangdong, with Korea and the Yemaek to the south, the Okchŏ tothe east, and Puyŏ to the north (高句麗在遼東之東、南與朝鮮、濊貊、東與沃沮、北與夫餘接).” According to “an Account of Eastern Okchŏ” of the “Records of Wei: An Account of theEasterners” in the Sanguozhi, “Eastern Okchŏ is to the east of the Kaema Mountains in Koguryŏ,by the eastern shore [facing] the great sea (東沃沮、在高句麗蓋馬大山之東、東濵大海.)”
4According to the Record of Seventh month in the fall of the 4th year of the reign of KingT’aejo (太祖大王四年秋七月条), Koguryŏ Annals, Samguk sagi, “They attacked EasternOkchŏ, took their land, towns, and villages, and expanded their borders to the Blue Sea in theeast (伐東沃沮、取其土地為城邑、拓境、東至滄海).”3

“Records of Wei: An Account of theEasterners ( 魏 志 東 夷 伝 )” in theSanguozhi (三国志, Records of the ThreeKingdoms)“Eastern Okchŏ is to the east of the
Kaema Mountains in Koguryŏ, by theeastern shore [facing] the great sea”

The Koguryŏ Annals (高句麗本紀) of theSamguk sagi( 三国史記 , history of thethree kingdoms)“They attacked Eastern Okchŏ, took theirland, towns, and villages, and expanded
their borders to the Blue Sea in the east”

4. The “Donghae Merchants” on the Kwanggaet’o Stele
Now, what about the word Donghae on the Kwanggaet’o Stele, erected in 414? TheKwanggaet’o Stele was erected by King Changsu (長寿王) of Koguryŏ to extol theaccomplishments of his father King Kwanggaet’o, so it is inscribed with tomb keepers
to protect the tomb of King Kwanggaet’o as well as their numbers. Among thosekeepers were the “Donghae Merchants.” 5 The South Korean government took notice ofthe word “Donghae” in the phrase “Donghae Merchants” and assumed that it signifiedthe Sea of Japan.
However, the Chinese character “ 賈 ” means merchants, therefore the Donghae
Merchants means only merchants in the place called Donghae (東海). It is unclear
where Donghae was, but it is rather arbitrary to assert that the Donghae merchants weremerchants in the Sea of Japan without further evidence.

The “Donghae Merchants (東海賈)” on the “Kwanggaet’o Stele (広開土王碑,a stone monument erected in 414)”
The South Korean government pays attention to the word “Donghae (東海)” in the“Kwanggaet’o Stele” and assumed it to signify the Sea of Japan without taking into
account the context in which the word Donghae was used. The passage around the word
Donghae on the Kwanggaet’o Stele is “Of the Donghae merchants, three are kugyŏnhouseholds and five are kanyŏn households (東海賈國烟三看烟五).” It has nothing to
do with the Sea of Japan.

5The passage around the phrase “Donghae Merchants” on the Kwanggaet’o Stele that theKorean government has cited as evidence is “Of the Donghae merchants, three are kugyŏnhouseholds and five are kanyŏn households (東海賈國烟三看烟五).”

5. The word “Donghae” in the P’alto ch’ongdo
The South Korean government regard the name “Donghae” in the P’alto ch’ongdo as
the Sea of Japan. Yet this is another distorted interpretation. The P’alto ch’ongdo is amap of all of Korea included in the Tongguk yŏji sŭngnam (東国輿地勝覧, Survey of
the Geography of Korea). It shows large rivers like the Han River and the Yalu River aswell as the names Donghae, Namhae (南海), and Seohae (西海) on the land. Seoul
interprets this Donghae to mean the Sea of Japan, but this is unfounded speculation,
because the afterword of the Tongguk yŏji sŭngnam specifies the following regardingthe P’alto ch’ongdo:“The comprehensive map in the beginning of the book (the P’alto ch’ongdo) is arecord of sacred peaks, famous mountains and large rivers listed in the Ritual Codes (祀典).”The large rivers and the Donghae depicted in the P’alto ch’ongdo referred to thelocations where state rituals took place as prescribed in the Ritual Codes. In fact, theDonghae shown in the P’alto ch’ongdo marks the location of the Donghae Shrine (東海神祠) in the Yangyang District Section (襄陽都護府条) of the Tongguk yŏji sŭngnam.
The Donghae Shrine was rebuilt in recent years as the Donghae Sanctum (東海神廟)”
shown in the photo below, and the P’alto ch’ongdo’s Namhae was also the Nanhae
Sanctum (南海神廟). The Donghae in the P’alto ch’ongdo marked the location of theDonghae Shrine, where state rituals took place, as specified in the afterword of theTongguk yŏji sŭngnam. This Donghae Shrine cannot be interpreted to be the Sea ofJapan.

The word “Donghae (東海)” in the P’alto ch’ongdo (八道総図, complete map of theeight provinces). The word “Seohae (西海)” and Namhae (南海)” are also in this map.

The “Donghae Sanctum (東海神廟),”that was rebuilt in recent years

The “Nanhae Sanctum (南海神廟).”

Moreover, regarding this Donghae, the afterword of the Tongguk yŏji sŭngnam statesthat “Each map of the eight provinces records the mountains guarding each area as wellas its four boundaries.” The maps depicting the administrative divisions bordering on
the Sea of Japan, “Hamgyŏng Province (咸鏡道),” “Kangwŏn Province (江原道),” and“Kyŏngsang Province (慶尚道),” all show their “four boundaries (四至四到)” andspecify adjacent areas.
At the eastern edges of the maps of “Hamgyŏng Province,” “Kangwŏn Province,” and“Kyŏngsang Province” there is the notation “Great Sea to the east (東抵大海).” This isbecause, at that time, Korean differentiated between coastal waters and the open sea,
which was called the Great Sea. This distinction between coastal waters and the open
sea comes from the fact that the Tongguk yŏji sŭngnam was compiled according to thesame editorial policy as the Da-Ming yitong zhi (大明一統志, Records of the Unity ofthe Great Ming.)“Kangwŏn Province (江原道),” in theTongguk yŏji sŭngnam (東国輿地勝覧,Survey of the Geography of Korea)
At the eastern edge of the map, there isthe notation “Great Sea to the east (東抵大海)”This tradition of differentiating between the two has
continued into modern times. Pak Ŭnsik (朴殷植) wrote thefollowing in his Painful History of Korea (韓国痛史, publishedin 1915):“Korea is a peninsular nation sticking out from southeast Asia.
Its borders are the Blue Sea (滄海) and are separated from theSea of Japan to the east as well as the Yellow Sea facing the two
Chinese provinces of Shandong and Jiangsu to the west.”

Painful History ofKorea (韓国痛史,published in 1915)
written by PakŬnsik (朴殷植)This was fourteen years before the International Hydrographic
Organization determined the names of the oceans and seas.
This shows that the Blue Sea was considered to be the coastal
waters off the Korean peninsula and the Sea of Japan wasconsidered to be the open sea offshore at that time. This is also
indicated by the wording “the East Sea, also known as theBlue Sea, a part of the Sea of Japan” in an article in theDong-A Ilbo ( 東亜日報 ), dated July 1, 1926. The South
Korean government argues that Korea was unable to assert in1929 that the name of the sea was the “East Sea” because it
was under Japanese colonial rule, but at the time of the Sea ofJapan’s inclusion into the Limits of Oceans and Seas, “EastSea” was used in Korea as a name for the coastal waters off
the Korean peninsula. It was only after WWII that “East Sea”
came to be mean the Sea of Japan. The headline of an article
The Dong-A Ilbo (東亜日in the Dong-A Ilbo, dated June 15, 1946, was “East Sea or報), dated July 1, 1926
Sea of Japan?” but that was because the debate about
whether to call it the Sea of Japan or the East Sea had just emerged.
6. The Name “Sea of Japan” was Used also in the Korean
Peninsula in the Second Half of the Nineteenth Century
Seoul repeatedly argues that the names “Sea of Japan” and“East Sea” should be used side by side because “East Sea” hasbeen used for 2,000 years. But it was not until around themid-twentieth century that the Sea of Japan came to be called
the East Sea in the Republic of Korea.
As mentioned above, the Korean patriot Pak Ŭnsik
differentiated between the Sea of Japan and the Blue Sea in his
Painful History of Korea, because the name “Sea of Japan” hadbeen also used on the Korean peninsula since the second half ofthe nineteenth century. The Yŏlchae ch’waryo (輿載撮要) from1896 states that Korea “is in eastern Asia. It borders the Bohai
Sea of the Qing to the west. It is connected with Manchuria tothe north, and is demarcated by the Sea of Japan to the east.”
Also the Tae-Han chiji (大韓地誌, Atlas of the Great Korean

The Yŏlchae ch’waryo(輿載撮要)Empire, published 1899), translated, edited, and compiled by Hyŏn Ch’ae (玄采) of theKorean Empire, states that Korea is “demarcated by the Sea of Japan in the east and thebeaches of the Yellow Sea in the west.”
As the South Korean government demands the name “Sea of Japan” be changed to“East Sea,” they emphasize the inappropriateness of “Sea of Japan” in light of Japan’scolonial rule. Yet, “Sea of Japan” was not decided solely by Japan. The Complete Mapof the Land and Sea of Great Japan, Along with Korea and Karafuto (大日本海陸全圖聯接朝鮮樺太) made in 1876 by Ojiri Hidekatsu (大後秀勝), a cartographer in theJapanese Navy, also says “日本海/JAPAN SEA,” but that is because it was drawn basedon British sea charts. Subsequently, the Taiwan suiro shi (寰瀛水路誌, published 1883)
and the Chosen suiro shi (朝鮮水路誌, published 1894) were also compiled by referring
to British nautical charts, maintaining the name “Sea of Japan.”

The Tae-Han chiji (大韓地誌, Atlas of the Great Korean Empire, published 1899)

7. Conclusion
The Japanese government’s statement that “Sea of Japan is the only internationallyestablished name” is based on consideration of the above history. The South Koreanemphasis of Japanese colonial rule is totally irrelevant here. Moreover, as I havediscussed at length, the word 東海 (Donghae) that the South Korean government
brings up as evidence in their challenge against the name “Sea of Japan” was either thecoastal waters off the Korean peninsula, names of places on land, the Yellow Sea, or theEast Sea of China. We should not refer to the Sea of Japan as the East Sea. It is also
inappropriate to use the names “Sea of Japan” and “East Sea” side by side asinternationally established names.
Finally, I sincerely hope that the South Korean government is able to realize that its
persistence in this naming issue even to the point of distorting historical facts has
become a source of confusion in the international community.

The Complete Map of the Land and Sea of Great Japan, Along with Korea andKarafuto (日本海陸全圖聯接朝鮮樺太) made by Ōjiri Hidekatsu (大後秀勝)※This leaflet represents its author’s view.