Masao Shimojo

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*
Abstract

Disagreement about the name of the Sea of Japan has persisted between Japan andSouth Korea since 1992. The basis for the South Korean assertion that the term
“East Sea” has been used for 2000 years to refer to the Sea of Japan is a passage
from a work known as Samguk sagi ( 三国史記 , History of the Three Kingdoms)that actually refers to the Yellow Sea, or the East China Sea. References to the East
Sea in historical maps such as the Pʼalto chʼongdo ( 八道総図 , complete map of theeight provinces) and the Aguk chʼongdo ( 我国総図 , complete map of Korea) havebeen distorted by South Korea to support its position. This paper points out theerrors in the South Korean interpretation of historical documentation and showsthat the term “East Sea” lacks the qualifications to replace the name Sea of Japan.
South Korea has repeatedly criticized Japan, alleging that use of the term East
Sea was excluded from the International Hydrographic Organizationʼs 1929 Limitsof Oceans and Seas because Korea was under Japanese rule at that time and was
deprived of the opportunity to assert the legitimacy of the name East Sea. A 1926
newspaper article in the Dong-A Ilbo ( 東亜日報 ) and the 1915 publication Painful
History of Korea ( 韓 国 痛 史 ) treated the “East Sea” as part of the Sea of Japanbecause the “East Sea” was then a designation for coastal waters off the Korean
Peninsula. Attempts to fabricate history and change the status quo will only cause
confusion in the international community and should not be tolerated.

D

1. Introduction

isagreement about the name of the Sea of Japan has persisted between Japan and South
Korea since the sixth UN Conference on the Standardization of Geographical Names(UNCSGN) in 1992. During this time, the Japanese government has consistently
maintained 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 “Seaof Japan,” has historically referred to only the coastal waters off the Korean Peninsula, not thewhole area of the Sea of Japan, and it does not qualify as an alternative to the name “Sea of Japan.”
However, Seoul continues to object to the use of “Sea of Japan” and insist on “East Sea.” This isbecause the South Korean government, which has occupied the Japanese territory of Takeshima*

Masao Shimojo is a visiting professor at Tokai Universityʼs Institute of Oceanic Research andDevelopment, and at the University of Shimane.

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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—)(Korean name: Dokdo) since 1954, has associated this territorial issue with the naming of the Sea
of Japan. The issue has been taken up diplomatically by 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 in Japanese 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 of Japan.”
The basis for the claim that “East Sea” has been used for 2000 years is the phrase “beachesof the East Sea” from the Book of the Sage King Tongmyŏng of the Koguryŏ1 Annals ( 高句麗本紀
始祖東明聖王条 ) in the Samguk sagi ( 三国史記 , History of the Three Kingdoms). The South
Korean side also argues that “East Sea” was excluded from the International Hydrographic
Organizationʼs 1929 Limits of Oceans and Seas, in spite of the nameʼs use for 2000 years before
that, because Korea was under Japanese rule at that time and thus deprived of the opportunity toassert the legitimacy of the name “East Sea.”
Probably because of a belief that it would be difficult to reach an agreement on using only “EastSea,” Seoul has argued since the 1997 conference of the International Hydrographic Organizationthat both “Sea of Japan” and “East Sea” should be used simultaneously.
However, as discussed in detail below, the word 東海 (Donghae, Dong means East andHae means Sea) that appears in the Samguk sagi, the Kwanggaet’o Stele (広開土王碑 , a stonemonument erected in 414), the P’alto ch’ongdo ( 八道総図 , complete map of the eight provinces),the Aguk ch’ongdo ( 我国総図 , complete map of Korea), and other pieces of evidence2 that havebeen identified by the South Korean government do not refer 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 of Japan) or the Yellow Sea or the East China Sea and has nothing
to do with the body of water 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) to the east of the
Korean Peninsula, but the western and southern coastal waters off the Korean Peninsula are also
indicated as Seohae ( 西海 , West Sea) and Namhae ( 南海 , South Sea), respectively. Seohae is apart of the Yellow Sea and Namhae is a part of the East China Sea, so they are names for stretchesof the Korean Peninsulaʼs coastal waters. In light of the South Korean governmentʼs argumentthat “East Sea” should be used instead of “Sea of Japan,” it would also be natural for Seoul toclaim that “Yellow Sea” and “East China Sea” should be replaced with “West Sea” and “SouthSea” 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) is located.
Moreover, the fact that the East Sea in the Aguk ch’ongdo refers to only the stretches of water
off the eastern coast of the Korean Peninsula can be verified by the Map of Liaodong and 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 the Korean Peninsula are
indicated to be the Korean West Sea ( 朝鮮西海 ), the southern coastal waters the Korean SouthSea ( 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 governmentʼs claims
that “East Sea” in the Aguk ch’ongdo refers to the whole area of the Sea of Japan are nothing otherthan an arbitrary interpretation of the map.
1

Koguryŏ is one of the three kingdoms whose historical record is compiled in the Samguk sagi. It wasestablished in the area north to the Yalu River in the 1st Century BC and expanded its territory to partsof both the Korean Peninsula and northeast China.

2

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

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Masao Shimojo

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
the Korean Peninsula, the western and southern coastal waters off the Korean
Peninsula are indicated as “Seohae ( 西海 , West Sea)” and “Namhae ( 南海 , SouthSea),” respectively. In light of the logic by the South Korean government, it shouldhave taken issue with Seohae and Namhae, too. But it has not done so.

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 governmentʼs arbitrar y interpretation ofliterature 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 2000 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 thephrase “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, the phrase“beaches of the East Sea” was used to refer to the area where the Sage King Tongmy ŏng, the43Japan Review Vol.4 No.1 Summer 2020

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—)

founder of Koguryŏ, moved to establish his new state. If so, we should be able to infer where theEast Sea was based on the territory of Koguryŏ at the time of its 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: An Account of the Easterners ( 魏志東夷伝 )” in the Sanguozhi ( 三国3
志 , Records of the Three Kingdoms), Koguryŏ was founded near the upper reaches of the Yalu
River in the 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 Sea
of Japan.
In fact, according to the Kogury ŏ Annals of the Samguk sagi, Koguryŏ did not defeat EasternOkchŏ, expand its territory eastward, and reach the Sea of Japan until the reign of King T’aejo( 太4祖 ), the sixth ruler after the Sage King Tongmyŏng. 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 2000
years ago, was not the Sea of Japan.

Records of Wei: An Account of the Easterners( 魏 志 東 夷 伝 ) in the Sanguozhi ( 三 国 志 ,Records of the Three Kingdoms)“ Eastern Okch ŏ is to the east of the Kaema
Mountains in Koguryŏ, by the eastern shore[facing] the great sea.”

The Koguryŏ Annals (高句麗本紀 ) of the
Samguk sagi ( 三国史記 , Histor y of theThree Kingdoms)“They attacked Eastern Okchŏ, took theirland, towns, and villages, and expanded
their borders to the Blue Sea in the east.”

3

According to “an Account of Kogury ŏ” of the “Records of Wei: An Account of the Easterners” in
the Sanguozhi, and “An Account of the Easterners” in the Hou Hanshu, “Kogury ŏ lies to the east of
Liangdong, with Korea and the Yemaek to the south, the Okchǒ to the east, and Puyǒ 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 EasternOkchǒ” of the “Records of Wei: An Account of the Easterners” in the Sanguozhi, “Eastern Okchŏ is to theeast 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 ).”4

According to the Record of 7th month in the fall of the 4th year of the reign of King T’aejo ( 太祖大王四年秋七月条 ), Koguryŏ Annals, Samguk sagi, “They attacked Eastern Okchŏ, took their land, towns, andvillages, and expanded their borders to the Blue Sea in the east ( 伐東沃沮、取其土地為城邑、拓境、
東至滄海 ).”

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4. The “Donghae Merchants” on the Kwanggaet’o Stele
Now, what about the word Donghae on the Kwanggaet’o Stele, erected in 414? The Kwanggaet’oStele was erected by King Changsu (長寿王 ) of Koguryŏ to extol the accomplishments of his father
King Kwanggaet’o, so it is inscribed with tomb keepers to protect the tomb of King Kwanggaet’o aswell as their numbers. Among those keepers were the “Donghae Merchants.”5 The South Korean
government took notice of the word “Donghae” in the phrase “Donghae Merchants” and assumed
that it signified the Sea of Japan.

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 theword Donghae on the Kwanggaet’o Stele is “Of the Donghae merchants, three arekugyŏn households and five are kanyŏn households ( 東海賈國烟三看烟五 ).” It has
nothing to do with the Sea of Japan.
However, the Chinese character “ 賈 ” means merchants, therefore the Donghae Merchantsmeans 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 were merchants in the Sea of Japan
without further evidence.

5. The word “Donghae” in the P’alto ch’ongdo

The South Korean government regards 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 a map 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 as well 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 thefollowing regarding the P’alto ch’ongdo:
5

The passage around the phrase “Donghae Merchants” on the Kwanggaet’o Stele that the Korean
government has cited as evidence is “Of the Donghae merchants, three are kugyŏn households and five
are kanyŏn households ( 東海賈國烟三看烟五 ).”45
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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—)“The comprehensive map in the beginning of the book (the P’alto ch’ongdo) is a record ofsacred 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 the locations
where state rituals took place as prescribed in the Ritual Codes. In fact, the Donghae shown in theP’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’ongdoʼs
Namhae was also the Nanhae Sanctum ( 南海神廟 ). The Donghae in the P’alto ch’ongdo marked
the location of the Donghae Shrine, where state rituals took place, as specified in the afterword of
the Tongguk yŏji sŭngnam. This Donghae Shrine cannot be interpreted to be the Sea of Japan.

The word “Donghae ( 東海 )” in the P’alto ch’ongdo ( 八道総図 , complete mapof the eight provinces). The word “Seohae ( 西海 )” and “Namhae ( 南海 )” are also inthis 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 states that
“Each map of the eight provinces records the mountains guarding each area as well as its fourboundaries.” 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 )” and specify adjacent areas.
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Masao Shimojo

At the eastern edges of the maps of “ Hamgy ŏ ng Province, ” “ Kangw ŏ n Province, ” and“Kyŏngsang Province” there is the notation “Great Sea to the east ( 東抵大海 ).” This is because,at that time, Korean differentiated between coastal waters and the open sea, which was called theGreat Sea. This distinction between coastal waters and the open sea comes from the fact that the
Tongguk yŏji sŭngnam was compiled according to the same editorial policy as the Da-Ming yitongzhi ( 大明一統志 , Records of the Unity of the Great Ming).
This tradition of differentiating between the two has continued into modern times. Pak Ŭnsik
( 朴殷植 ) wrote the following in his Painful History of Korea ( 韓国痛史 , published in 1915):“Korea is a peninsular nation sticking out from southeast Asia. Its borders are the Blue Sea (滄海 ) and are separated from the Sea of Japan to the east as well as the Yellow Sea facing the two
Chinese provinces of Shandong and Jiangsu to the west.”“Kangwŏn Province ( 江原道 )” in the Tonggukyŏji sŭngnam ( 東国輿地勝覧 , Sur vey of theGeography of Korea)
At the eastern edge of the map, there is the notation“Great Sea to the east ( 東抵大海 ).”47
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Painful History of Korea ( 韓国痛史 , published in 1915)
written by Pak Ŭnsik ( 朴殷植 )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—)

The Dong-A Ilbo ( 東亜日報 ), dated July 1, 1926
This was fourteen years before the International Hydrographic Organization determined thenames 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 was considered to be the open sea offshoreat that time. This is also indicated by the wording “the East Sea, also known as the Blue Sea,a part of the Sea of Japan” in an article in the Dong-A Ilbo (東亜日報 ), dated July 1, 1926. The
South Korean government argues that Korea was unable to assert in 1929 that the name of thesea was the “East Sea” because it was under Japanese colonial rule, but at the time of the Sea ofJapanʼs inclusion into the Limits of Oceans and Seas, “East Sea” was used in Korea as a name forthe coastal waters off the Korean Peninsula. It was only after WWII that “East Sea” came to mean
the Sea of Japan. The headline of an article in the Dong-A Ilbo, dated June 15, 1946, was “East Sea
or 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 theSecond Half of the Nineteenth Centur y

Seoul repeatedly argues that the names “Sea of Japan” and “East Sea” should be used side by side
because “East Sea” has been used for 2000 years. But it was not until around the mid-twentiethcentury 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 Japanand the Blue Sea in his Painful History of Korea, because the name “Sea of Japan” had been also
used on the Korean Peninsula since the second half of the nineteenth centur y. The Yŏlchae
ch’waryo ( 輿 載 撮 要 ) from 1896 states that Korea “is in eastern Asia. It borders the Bohai Seaof the Qing to the west. It is connected with Manchuria to the 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 Empire,
published 1899), translated, edited, and compiled by Hyǒn Chʼae ( 玄采 ) of the Korean Empire,states that Korea is “demarcated by the Sea of Japan in the east and the beaches of the Yellow Sea
in the west.”
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The Yŏlchae ch’waryo( 輿載撮要 )The Tae-Han chiji ( 大韓地誌 , Atlas of theGreat Korean Empire, published 1899)

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 Japanʼs colonial rule. Yet, “Seaof Japan” was not decided solely by Japan. The Complete Map of 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 Ōjiri Hidekatsu( 大後秀勝 ), a cartographer in the Japanese Navy, also says “日本海 /JAPAN SEA,” but that is
because it was drawn based on 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.”

7. Conclusion

The Japanese governmentʼs statement that “Sea of Japan is the only internationally establishedname” is based on consideration of the above history. The South Korean emphasis of Japanesecolonial rule is totally irrelevant here. Moreover, as I have discussed 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 the coastal waters off the Korean Peninsula, names of places
on land, the Yellow Sea, or the East Sea of China. We should not refer to the Sea of Japan as theEast 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 asource of confusion in the international community.
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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—)

The Complete Map of 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 by Ōjiri Hidekatsu ( 大後秀勝 )50Japan Review Vol.4 No.1 Summer 2020