Dokdo and Japanese Naval Records
The Japanese Warship Niitaka´s logbooks provide some insight about Dokdo Island during the early 20th century.
In the year 1904, the waters between Korea and Japan became the scene of fierce naval conflicts. Russian battleships from the Vladivostok fleet entered the waters of the Korea Strait and sank Japanese transport ships one after another. These events turned the once peaceful waters around Ulleungdo-Dokdo into area of intense sea battles. Dokdo Island went from being a worthless collection of rocks to an islet that held the key to controlling the vital shipping lanes of the Korea Strait. On July 5, 1904 the Japanese built watchtowers on Ulleungdo Island and it was decided to link them with the Japanese Navy anchorage in Chukpyeon Bay on the Korean mainland by military submarine cables. Ulleungdo's two watchtowers were one at the southeastern part (East tower with six men posted) and the other at the northwestern part (West tower with six men posted). Their construction started on August 3, 1904, and the operation began on September 2 of the same year. The submarine cable was installed under the threat of the Vladisvostok fleet and completed on September 25 of the same year. Through this cable, the watchtowers on Ulleungdo were able to communicate directly with the naval base in Sasebo through the Korean mainland. The stationing of a Japanese military force on Ulleungdo meant the further violation of Korean sovereignty over the island where the Japanese had already built its superior position. The Imperial Navy had already paid attention to Dokdo´s value well before Nakai Yozaburo had submitted a request to the government to hunt seals there and had already started taking action before the Japanese government had decided to incorporate Dokdo.
This sketch from the logbook of the Niitaka clarifies why old Korean documents often called Dokdo ´Sambongdo´ or ´Three Rock Island´.
The logbook of the Niitaka on September 24, 1904 reads as follows: "Koreans call the Liancourt Rocks Dokdo while the Japanese fishermen call it Lianco. It is possible to moor the vessels between the two rocks, but a small boat is usually pulled ashore. When the sea is rough and it is difficult to anchor, boats usually take refuge on Ulleungdo until the weather calms down.. Those who come from Ulleugdo to catch sea lions use a Japanese vessel that can load 60 to 70 koku (307 to 358 bushels) and build huts to stay there for about 10 days each time: The catch is plentiful: and the number of the crew sometimes exceeds 40 to 50, but they talk about the lack of fresh water..." Here in this documented log book we can see that the Koreans had been using the name Dokdo before the Shimane Prefecture inclusion. In addition, this journal proves Koreans were both cognizant and involved with the island. Thus the island was not a terra nullius as Japanese have claimed.
On November 13, 1904, the Japanese Naval General Staff ordered the warship Tsushima to inspect Dokdo and see whether it was suitable for the installation of a telegraphic station there. It was a survey to examine whether it was possible to build a watchtower there to be linked by submarine cable with Ullungdo. The Tsushima arrived at the Liancourt Island on November 20, and this was the first-ever survey of Dokdo by the Japanese government. The Tsushima´s captain reported that although there was some topographical difficulty, it was possible to build a structure on the East Islet.
The Japanese government´s interest in Dokdo at that time was only for its military value. As it was absolutely impossible to engage in construction work on Dokdo during the winter, Japan, without starting the work, faced the decisive battle with Russia´s Baltic fleet. As the seas around Ullungdo and Takeshima/Tokdo became the main sea battleground, the island´s military value came to be highly valued.
On May 27th 1905 the Japanese Navy engaged and obliterated the Russian Baltic Fleet in what was known as the Battle of Tsushima. As the seas around Ulleungdo and Dokdo were the main sea battleground it became even more clear Dokdo had significant military/strategic value. Not coincidentally, the Japanese Navy drafted a comprehensive plan for facilities in the East Sea (including both Ulleungdo and Dokdo) three days later on May 30th 1905.
The warship Hashitade was ordered to go to Dokdo for a more detailed survey. The watchtower on Ulleungdo started on July 14th 1905 and was completed on August 16th while that on Dokdo began on July 25th and was completed on August 19th. In 1905, a network of military communication lines were completed from the Korean mainland-Ulleungdo-Dokdo-Matsue Japan.
Japanese Naval PublicationsThere are other references from the Japanese Imperial Navy such as the "Sealanes of the World" publications that also make references to the Korean name "Dokdo" in the early 1900s. The 1907 edition states: "Takeshima (Liancourt Rocks) The Koreans call this island Dokdo and Japanese fishermen, Liancoto. When the warship Tsushima surveyed this island November in the 37th year of Meiji (1904) there were small thatched huts for fishermen on the East Islet but they were said to be destroyed by wind and waves. Every summer dozens of people come from Ulleungdo to catch sea-lions. They build huts on this island and stay there for about 10 days each time."
These Japanese naval maps showing Japan´s territorial waters excluded Dokdo/Takeshima (from Korea Observer)
In March 1889, Japan began to publish the Nihon Suroshi (Japanese Sealanes) was made independent and was published successively from 1892. This publication shows not only Taiwan and Hoko shoto (Pescadores) which Japan gained as its new territory under the Shimonoseki Peace Treaty in 1895, but also the northernmost island of Senshuto in the Chishima Retto (Kuriles). But it does not include the other side of the Taiwan Strait and the Kamchatka Peninsula. In other words, the geographical coverage in the publication is limited to Japan´s territory and territorial waters. What is important is the fact that Dokdo does not appear in the East Sea (Sea of Japan) in this publication. Given the fact the Japanese sea maps at this time accurately show the position of the island, it is unthinkable that the Japanese Imperial Navy did not know its location. As of 1900 the Japanese Navy clearly excluded the island from Japan´s territory. Moreover, the 1894 and 1897 editions of the Chosun suiroshi (Korean Sealanes) by the Japanese Navy show Liancourt Rocks/Dokdo along with Ulluengdo. There is no doubt the Japanese Naval hydrographic authorities were aware Dokdo belonged to Korea. In brief, after the Meiji Restoration the Japanese government had not expressed any particular interest in Takeshima/Dokdo. It is clear that all the Japanese government organs involved regarded the island as Korea´s along with Ulluengdo though the degree of their cognizance differed.
This 1895 map by Shimizu Ikunosuke defines Japan´s western limit as Oki Island (map's border at top)
In 1876 cartgrapher Asano Meido also considered Oki Island as the western boundary of Japan (border of the map, at top)
Area on this modern map of Japan´s coast gives reference to aforementioned 19th century maps and Navy charts.
1891 Shimane Prefecture map, with Oki Island, and no other islands inclusive.
1908 Shimane Prefecture map. Even after the ´incorporation´ of Dokdo, the island, which was not traditionally considered part of Shimane, is not on this map.