Issue of the Name of the Sea of Japan
Overview of a Study of Maps Possessed by the U.S. Library of Congress

August, 2005

1. The Ministry of Foreign Affairs of Japan conducted a study from December 2004 through March 2005 of the maps published from the 14th to 19th centuries in possession of the United States Library of Congress with regard to the naming on maps of the maritime region known as the Sea of Japan. The study was undertaken as a means to confirm the assertion of Japan that "the name "Sea of Japan" became established and accepted in Europe since the beginning of the 19th century at a time when Japan was still under its policy of isolation, being unable to exert international influence."
2. On the other hand, Republic of Korea"s (ROK) asserted that the name "Sea of Japan" became dominant as a result of Japan"s imperialism and colonialism during the first half of the 20th century and that both the "East Sea" and "Sea of Japan" were widely used in world maps until the mid- to late 19th century. The ROK cited its own study of old maps in the U.S. Library of Congress as the basis of its claims. According to the study on 228 old maps by the ROK, a name was recorded for the region of the sea of Japan on 103 maps, of which 68 maps, or 66% bore the name "Sea of Korea", and only 14 maps, or 14% bore the name "Sea of Japan")
3. The findings of the research undertaken by the Ministry of Foreign Affairs of Japan concerning the maps in the U.S. Library of Congress are as follows:

1. Purpose of the Study

(1)	Japan has consistently asserted the legitimacy of the name "Sea of Japan" and its major grounds are the following three key points. (a) At present, the name "Sea of Japan" is internationally established. (b) Historically, the name "Sea of Japan" became established and accepted in European maps since the beginning of the 19th century. (c) In view of the methodology for geographical naming, the name "Sea of Japan" is appropriate.
(2)	Regarding the historical perspective mentioned above in (1).(b), two researchers at the Geographical Survey Institute studied over 200 antique maps published in Europe. As a result, they discovered that until the late 18th century, various names were used to refer to this sea, such as the "Sea of China," "Oriental Sea," "Sea of Korea" and "Sea of Japan." However, it has been confirmed that the name "Sea of Japan" came to be used with overwhelming frequency mostly in European maps since the beginning of the 19th century *1. This fact was confirmed through the studies conducted by the Ministry of Foreign Affairs of Japan on maps possessed by the British Library and the University of Cambridge and the Bibliotheque Nationale de France *2. From the end of the 18th century to the beginning of the 19th century French, British, Russian and other explorers investigated the areas surrounding the Sea of Japan and discovered that topographically the Sea of Japan is separated from the Pacific Ocean by the Japanese Archipelago. As a result of this discovery, the name "Sea of Japan" came into regular usage in European maps. This view is supported by many researchers. Notes: *1) Refer to the pamphlet by the Ministry of Foreign Affairs of Japan "Sea of Japan." [PDF] *2) Refer to the homepage of the Ministry of Foreign Affairs of Japan " The study of maps possessed by the British Library and the University of Cambridge" and "The study of maps possessed by the Bibliotheque Nationale de France" [PDF]
(3)	In order to further investigate the validity of the above assertion, the Ministry of Foreign Affairs of Japan conducted a field study to see whether or not the name "Sea of Japan" is established and accepted in European maps, particularly those that were published in the early to mid-19th century. This study was conducted at the U.S. Library of Congress which has a wealth of cartographical references.
(4)	The background of the study is the Republic of Korea's (ROK) assertion that the name "Sea of Japan" became dominant as a result of Japan's imperialism and colonialism during the first half of the 20th century and that both the "East Sea" and "Sea of Japan" were widely used in world maps until the mid- to late 19th century. The ROK cited its own study of antique maps in the U.S. Library of Congress as the basis of its claims. According to the study by the ROK, out of 228 antique maps created before 1800, 103 maps covered the region of the sea of Japan, of which 68 maps, or 66% bore the name "Sea of Korea" or "East Sea", and only 14 maps, or 14% bore the name "Sea of Japan")

2. Outline of the Study and Conclusions

(1) Outline of the Study

The Ministry of Foreign Affairs of Japan conducted a study between December 2004 and March 2005 of the naming of the Sea of Japan maritime region on maps held by the U.S. Library of Congress. Summarized results of the study are as follows:

(a)	The study was performed in cooperation with the Embassy of Japan to the United States by dispatching study personnel to the Geography and Maps Department of the U.S. Library of Congress.
(b)	The subjects of the study were all maps *1 and atlases that cover the region of the Sea of Japan. *2 Motif style maps or picture postcard maps or other such products published for objections other than showing regional characteristics were excluded from the study.
(c)	The maps and atlases surveyed in the study ranged from the oldest held by the Library published in 1300 *3 to those published up until the year 1900.
(d)	The primary survey method the researcher adopted for this study was to study actual maps or atlases that had been converted to microfilm. Only a few of the maps were examined by searching an electronic database based on the Library catalog numbers. *4 Such method was adopted since maps and atlases acquired by the Library prior to 1968 were, in general, registered by the catalog numbers instead of the electronic database, thereby making it impossible to identify maps and atlases subject to this study using only electronic databases. *5
(e)	With regard to the maps and atlases selected as described in (d), the researchers actually viewed the maps, recorded the appellation of the region, the date of publication, the publisher, and the nationality of the publisher, and made photocopies either with a digital camera or photocopier.

Notes:

*1) For purposes of this study, "maps" were the "single sheet" and "sheet map" as categorized by the Library.

*2) For purposes of this study, "atlases" were those classified by the Library as a "World Atlas". This was a broad category including those "World Atlases" containing maps showing all the regions of the world and those showing only regions from certain parts of the world.

*3) The oldest of those maps held by the geography-map department of the Library was titled "Empire de Mongols" and since the date of publication was listed as "1300-1400," the exact date of publication is unknown.

*4) For details, see http://catalog.loc.gov

*5) It was therefore impossible to employ a random sampling method through use of electronic data when surveying old maps held by the Library. The present study accordingly provided a more objective method for surveying old maps. There is no other way than to look at each map, one by one. However, the Government of Korea also conducted a similar study at this library and their conclusions were based on part of the maps possessed by the library extracted through a certain method.

(2) Conclusions

The study's conclusions are as follow:

(a)	There were a total of 1728 pieces showing the Sea of Japan region on maps and atlases published between 1300 and 1900. Among them, 1435 pieces showed some names for the region known as Sea of Japan. Among the 1453 pieces, 1110 referred to the area as the Sea of Japan or Japan Sea, which corresponds to 77.4% of the total.
(b)	On the other hand, 188 of the 1435 pieces, referred to the Sea of Japan region as the "Korean Sea," (13.1% of the total), 22 pieces (1.5%) referred to it as the "China Sea,"20 pieces (1.4%) referred to the region as the "Oriental Sea," and only 2 pieces (0.1%) as the " East Sea".
(c)	Among the maps that show more than two names, 14 pieces (0.9%) referred to the area as the "Sea of Japan/Korean Sea.", 7 pieces (0.5%) as the "Sea of Japan/Oriental Sea.", 4 pieces (0.3%) as the "Oriental Sea/Korean Sea.", 1 piece (0.07%) as the "Sea of Japan/China Sea.", and 8 pieces (0.6%) showed other than the above-mentioned names.
(d)	Looking at the results based upon the era of publication of the map or atlas, those published up through the 18th century by the nations of the world used various appellations for the Sea of Japan region including "Sea of Japan", "Oriental Sea", "Korean Sea", etc. However, among those published in the 19th Century, 82.4% or 1059 map pages used the term "Sea of Japan" or "Japan Sea". Specifically, there were 563 maps published in the 19th century during Japan's isolation policy (up until 1860, for the sake of convenience), and among them, 74% of 417 pieces used the term "Sea of Japan". These facts reinforce the validity of Japan's argument that the name "Sea of Japan" had been standardized in Europe and the U.S.A since 19th century, when Japan, under its isolation policy, could exert no international influence.

(Table)
Conclusions of a Study of Maps Possessed by the U.S. Library of Congress

Country	Until 1600	1601-1700	1701-1800	1801-1860	1861-1900	Total	Percentage
Japan	1	3	47	417	642	1110	77.352
Korea Sea	0	2	94	82	10	188	13.101
China Sea	3	11	8	0	0	22	1.533
Eastern Sea	0	0	1	0	1	2	0.139
Oriental Sea	0	4	14	1	1	20	1.394
Tartar Sea	0	0	0	3	0	3	0.209
Tessot Sea	0	0	2	2	1	5	0.348
Japan/Korea	0	0	3	11	0	14	0.976
Japan/Oriental	0	0	7	0	0	7	0.488
Japan/China	0	0	1	0	0	1	0.070
Eastern/Corea	0	0	4	0	0	4	0.279
N.D.	0	3	7	18	19	47	3.275
No Entry	32	80	109	29	43	293
Others	0	3	4	0	5	12
Total	36	106	301	563	722	1728

(3) Analysis of the study implemented by the ROK

Based on the results of this study, the following questions arise when examining the results of the similar study implemented by the Government of the ROK at the United States Library of Congress in 2002 (Note 1).

(a)	The criteria by which the ROK selected maps for inclusion in its study are unclear. The ROK survey at the Library of Congress is said to have included 228 maps published prior to 1800, but there are a total of 445 maps published prior to 1800 that are in the possession of the library, which would mean that the ROK utilized only 51% of the total maps available in its study. In addition, since all the maps published in that period are generally unavailable in an electronic database format, it is impossible to use electronic data to randomly select maps for study. Besides this, the Library of Congress personnel confirmed that in the period from 2002 to 2003 when the study was taking place, there was not sudden increase of the number of maps and atlases possessed by the library.
(b)	There are doubts about the objectivity of the results of the study by the ROK. In their study, the ROK concludes that among the maps published between the 17th and 19th centuries, "the most frequently used names were those associated with Korea, such as Sea of Korea or East Sea." However, in the study implemented by the Ministry of Foreign Affairs of Japan, out of a total of 1,694 maps and atlases published between the 17th and 19th centuries, maps using Korea-related nomenclatures such as "Sea of Korea," or "East Sea" numbered 235, or 13.9% of the total, including maps that inscribe two names: "Sea of Japan" and "Sea of Korea." In addition, 1,058 maps, or 62.5% of the maps published during the period in question, bear the name "Sea of Japan," which makes it difficult to understand the ROK's assertion that, "the most frequently used names were those associated with Korea."
(c)	In addition, the ROK has asserted that, "the name 'Sea of Japan' came into dominant use as a result of Japan's imperialism and colonialism during the first half of the 20th century," however, the study implemented by the ROK does not include maps from the first half of the 20th century, which is the period on which the ROK claims are centered.

Note 1: Refer to East Sea in Old Western Maps with Emphasis on the 17-18th Centuries, and East Sea - A name with 2000 years of history, The Society for East Sea: The Korean Overseas Information Services, Government of the Republic of Korea.

(4) Reference to the additional data

(a) Call number (recorded in the far left column):

The United States Library of Congress stores antique maps under the following classifications: Asia, Russia (Asian and Siberian regions), Central Russia, China, East Asia, Japan, Korea, Oceania, Pacific, and World. The researchers put numbers to maps in each classification in chronological order among maps and atlases relevant for the study.

(b) Map name, publisher, publishing company

(c) Country of publication

The country of publication is determined by the country in which the publishing company is located. For example, if the creator of the map is a British national, and the map was published in France, the country of publication is classified as France.

(d) Method of judging the year of publication

The maps and atlases that were subject to the study were classified in chronological order in the library's collections. If a map recorded as "18--" was stored between a map bearing the year "1800" and another bearing the year "1801," for example, the map in question was for statistical purposes considered to have been published after 1800 and before 1801.

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