Siebold incidentDeported to country for taking out map

Philipp Franz von Siebold was a physician active during the Edo period and a famous naturalist. He is known for spreading Western medicine in Japan, but in 1828, he was found guilty of plotting to take Japanese maps overseas, which was prohibited by the country, and was deported the following year. This incident, known as the "Siebold Incident," led to the punishment of about 50 people involved, but why did it happen? This time, we will explain this mysterious incident in an easy-to-understand way.

Who was Siebold, the protagonist of the Siebold Incident?

Philipp Franz von Siebold (Siebold) came to Japan in the late Edo period as a doctor attached to the Dutch trading post. He is known for opening a private school called Narutaki Juku in Nagasaki and imparting Western medicine to the Japanese people, but he was not originally Dutch, but was originally from Würzburg, a religious city in south-central Germany.

Siebold was born in 1796 to an aristocratic family of doctors, and studied medicine, zoology, botany, ethnology, etc. at the Medical Faculty of the University of Würzburg. It is said that it was from this time that Siebold became interested in the Orient. After graduating, he worked as a local doctor for a time, but in 1822 he was appointed "First Surgeon Major of the Dutch East Indies Army." He came to Japan in 1823 and began working as a doctor at the Dutch trading post on Dejima in Nagasaki.

Siebold was not just a doctor, but a surgeon-major. For this reason, there is a theory that he received secret orders from the Netherlands to investigate Japan. He was a spy.

What was Siebold's relationship with the Netherlands?

Around the time of Siebold's arrival in Japan, the Netherlands had been granted re-independence as the "United Kingdom of the Netherlands" at the Congress of Vienna (* Bunka 11-12 in Japan) held from September 1814 to June 1815, and was just beginning to move forward under a new system. The Congress of Vienna was a conference held with the participation of European countries in order to restore order in Europe after the Napoleonic Wars. In fact, as a result of the Napoleonic Wars, the Netherlands was annexed by France along with the Dutch East Indies (now Indonesia), and for a while the only part of the country known as the Netherlands was Dejima in Nagasaki.

Although the Netherlands managed to achieve independence, the first urgent task was to restore its finances. For this reason, they considered reconsidering trade with Asia, and set their sights on Japan, which had been isolated from the rest of Europe and did not trade with other European countries. They wanted to provide Japan with knowledge and technology of Western medicine, while also studying Japan as a trading nation.

Meanwhile, Siebold left the Netherlands for Batavia (Jakarta), where he served as a military doctor and also took up the post of natural science investigator for the East Indies. During his stay, he expressed to the Governor-General of the Dutch East Indies that he wanted to study Japan. Thus, the Dutch intentions and Siebold's wishes coincided, and Siebold set off for Japan. He arrived in Japan in August 1823 (Bunsei 6) and was appointed doctor at the Dutch trading post on Dejima in Nagasaki.

In fact, when he entered the country, Siebold's Dutch had an unnatural accent, which made the Japanese suspicious of him. However, Siebold managed to get away with it by saying, "I come from the mountainous region of the Netherlands (= a mountain Dutchman) so my accent is there." Most of the Netherlands is made up of lowlands below sea level, and there are almost no mountains, but since the Japanese at the time were not familiar with the Netherlands, he was able to get away with it.

Siebold in Japan

As a physician attached to the trading post, Siebold worked to manage the health of the trading post's employees, but he soon became known as an excellent physician and his name was known to Takahashi Shigekata, the Nagasaki magistrate at the time. Shigekata allowed Japanese doctors and others to enter Dejima to study under Siebold, and also allowed Siebold to examine ordinary people outside Dejima and collect medicinal herbs.

This led Siebold to introduce Western medicine to many Japanese people. The Western medicine that Siebold introduced included smallpox vaccines and cataract surgery using belladonna. It must have been a constant source of surprise for the Japanese people at the time.

However, Siebold did not simply impart knowledge of Western medicine. His goal was to study Japan, and he obtained information about Japan, including Japanese plants, from his students. He wrote "Natural History of Japan" just over three months after arriving in Japan, and created a medicinal herb garden in Dejima, where he devoted himself to his research. Incidentally, in 1825, he was officially allowed to open a botanical garden in Dejima, and cultivated over 1,400 species of plants until he left Japan due to the Siebold Incident.

In 1824, the Nagasaki Magistrate allowed education outside of Dejima, and Narutaki Juku (Narutaki, Nagasaki City, Nagasaki Prefecture) was opened on the outskirts of Nagasaki. Many doctors and scholars from all over Japan gathered here. Representatives included Takano Choei, his first disciple and Dutch scholar, Ito Genboku, a Dutch medicine doctor who later rose to become an official physician in the Edo Shogunate, Ito Keisuke, Japan's first doctor of science, and Ninomiya Keisaku, known for raising Kusumoto Ine, the daughter of Siebold and Japan's first female doctor (obstetrician).

The Siebold Incident: Part 1 - The trigger: the visit to Edo

The trigger for the Siebold Incident was a visit to Edo in 1826 (Bunsei 9). Siebold was to accompany a party led by the Dutch chief of the Dutch factory (kapitan) on a court visit to Edo. This was a visit by the chief of the Dutch factory to Edo and to meet with the shogun to express gratitude for trade between Japan and the Netherlands, and was held once every four years at the time. Since foreigners were normally not allowed to leave Nagasaki, the visit to Edo was a great opportunity to see Japan.

A visit to Edo usually lasted around 90 days, but since Siebold's purpose was to investigate Japan, he lobbied for a longer stay. As a result, his 162nd visit to Edo in 1826 took from February 15th to July 7th, an astonishing 143 days, the longest on record.

The trip took them overland from Nagasaki to Saga, Fukuoka, Shimonoseki, and then aboard a ship to Hyogo. They passed through Osaka and Kyoto, and arrived in Edo via the Tokaido. During this time, Siebold was so absorbed in his research into natural history that he even called his palanquin a "floating laboratory." Also accompanying the group were geologist Bürger as a secretary and Kawahara Keiga as a painter. His student and physician Ko Rasai also joined and assisted Siebold in his research.

During his travels, Siebold collected a wide range of items, including plants, folk tools, crafts, and paintings and calligraphy, and also measured Japan's latitude, longitude, and altitude, and investigated various aspects of Japan, including botany, geography, and astronomy. In his notes, he recorded that he surveyed the Kanmon Straits in Shimonoseki. He also provided many Japanese people with knowledge of Western medicine along the way.

Siebold Incident 2: Obtaining a prohibited map of Japan in Edo

In Edo, he had an audience with Shogun Tokugawa Ienari and interacted with doctors and scholars. On this occasion, Ezo (Hokkaido) explorer Mogami Tokunai secretly provided him with a rough map of the Ezo Sea and Sakhalin Island, and they continued to interact with each other. He also interacted with Takahashi Kageyasu, an astronomer, and Kondo Juzo and Mamiya Rinzo, who had explored Ezo and Northern Ezo (Kakhalin).

During his stay in Edo, Siebold made a deal with Takahashi Kageyasu to exchange documents and maps owned by Siebold, such as "A Voyage Around the World" by Russian naval admiral and explorer Krusenstern, and a new map of the Dutch Indies, for Japanese maps. At the time, it was strictly forbidden to take Japanese maps overseas, but Kageyasu decided to make the exchange because "A Voyage Around the World" clarified unknown points about Sakhalin, and he believed that obtaining a map of the Dutch Indies would be in the national interest.

Some researchers also postulate that Takahashi Kageyasu planned to have a copperplate map of Japan printed in the Netherlands or in Batavia, and showed the map to Siebold to place an order for printing. This theory is based on the diary of the chief of the Dutch trading post.

On May 15, Takahashi Kageyasu handed Siebold a contraband map of Japan. In Siebold's notes, he wrote, "Globius (Takahashi Kageyasu) came and showed me a beautiful map of Japan." The map of Japan handed over at this time was a miniature version of Ino Tadataka's "Dai Nippon Enkai Kochi Zenzu" (Complete Map of the Great Japanese Coastline) and a copy of a map of Sakhalin. In addition, Kageyasu lent Siebold books such as those by Mamiya Rinzo at his request.

After his stay in Edo, Siebold returned to Nagasaki, but the amount of artefacts he had acquired during his time as Edo counsellor was enormous. These artefacts were sent by ship from Nagasaki to the Netherlands in the autumn.

The Siebold Incident 3: The incident occurred just before returning to Japan

In 1827, Siebold came to Japan and married his Japanese wife, Taki Kusumoto, and had a daughter, Ine Kusumoto. The Siebolds were very happy together, but in September, the Dutch East Indies government decided to return Siebold to Batavia. Siebold was to return to Batavia in 1828. Just before that, it was discovered that Siebold was trying to take banned maps of Japan overseas.

In fact, there are several theories as to why this was discovered. The commonly held belief is that the removal of the maps was discovered when a ship that had set out ahead of Siebold and was heading for the Netherlands was wrecked during a major storm in September 1828. Some of the cargo that washed up on a Japanese beach included a map of Japan that had been banned by the shogunate. The shogunate requested that Siebold return the maps, but he refused, so the shogunate banned him from leaving the country, and he was ultimately banished from Japan.

However, in recent years, a new theory that refutes this common belief has been gaining attention. According to the diary of Meylan, who was the head of the Dutch trading post at Dejima at the time, the only thing the ship had on board at the time it ran aground was about 30 tons of copper used as ballast, and no cargo.

According to the new theory, the incident began when Mamiya Rinzo reported a package sent by Siebold to the shogunate. Although Mamiya Rinzo is known as an explorer, he was actually a shogunate official, or secret agent.

The incident began when Siebold sent a letter to Takahashi Kageyasu, as well as a letter and gift to Rinzo. According to a copy of Siebold's letter, he asked Kageyasu to intercede for Rinzo in order to obtain the specimens of Ezo that Rinzo had. Kageyasu obediently forwarded the letter to Rinzo, but Rinzo thought that exchanging personal items with a foreigner might violate the national ban, so he reported it to his superiors in the shogunate. However, Kageyasu did not report his relationship with Siebold to the shogunate, and the shogunate, suspicious of the close relationship between the two men, began an investigation.

A search of Kageyasu's house resulted in the seizure of four copies of Krusenstern's Voyage Around the World and copperplate maps of the Netherlands. Kageyasu was then arrested and it was discovered that he had given the maps to Siebold.

As a result, the shogunate ordered the Nagasaki Magistrate's Office to interrogate Siebold and to search his home, where the maps were also found. However, Siebold maintained that his purpose was academic research and refused to return the maps. In response, the shogunate did not clear Siebold of the espionage charges, but confiscated the maps, exiled him from the country, and banned him from traveling again. In fact, Siebold had planned to return to Japan three years later, but this was no longer possible, and he had to return to the Netherlands, leaving his wife and son behind.

Meanwhile, Kageyasu was arrested and incarcerated in the Tenmacho Prison, where he died in prison in March 1829. His body was salted and then decapitated. In addition, the shogunate arrested and punished about 50 Japanese people connected to Siebold, including Ninomiya Keisaku, Korasai and other members of the Narutaki School, Kawahara Keiga, and even interpreters. Siebold denied their responsibility and tried to intervene by offering to naturalize as a Japanese citizen and remain in Japan for the rest of his life, but the shogunate did not accept his request. On December 30, 1829, he left Japan, leaving his wife and daughter behind.

After the Siebold Incident: Publication of the Map of Japan and Siebold's Return to Japan

Although the map of Japan was confiscated by the shogunate, Siebold actually secretly made a copy of it. In 1840, he published a map of Japan in Leiden, Netherlands, and this copy was recently discovered by Siebold's descendants, causing quite a stir.

In addition, based on his collections, including specimens sent to the Netherlands and his stay in Japan, he published a large-scale work titled "NIPPON" in 13 volumes over 20 years from 1832. It is said that Commodore Perry also used this book as a reference when he visited Japan.

After returning to the Netherlands, Siebold continued to exchange letters with his wife. Furthermore, about 30 years later, on August 14, 1859 (6th year of the Ansei era), Siebold returned to Japan as an advisor to a Dutch trading company. This was because he was exempted from punishment under the Treaty of Amity and Commerce between Japan and the Netherlands that had been concluded the previous year. Siebold began working as a diplomatic advisor to the shogunate, but was dismissed after actively providing information about Japan to other countries. He left Japan in disappointment, but remained very interested in Japan throughout his life.