, also known as Kutsuki Oki-no kami Minamoto-no Masatsuna, was a hereditary Japanese daimyo

Daimyo

is a generic term referring to the powerful territorial lords in pre-modern Japan who ruled most of the country from their vast, hereditary land holdings...

 of Oki

Oki Province

was an old province of Japan which is now Shimane Prefecture. It was sometimes called . Oki province consisted of the Oki Islands in the Sea of Japan, located off the coast of the provinces of Izumo and Hōki....

 and Ōmi

Omi Province

is an old province of Japan, which today comprises Shiga Prefecture. It was one of the provinces that made up the Tōsandō circuit. It is nicknamed as .Lake Biwa, Japan's largest lake, is located at the center of the province...

 with holdings in Tamba

Tamba Province

was an old province of Japan. The ambit of its borders encompassed both the central part of modern Kyoto Prefecture and the east-central part of Hyōgo Prefecture. It was sometimes called , with Tango Province...

 and Fukuchiyama. His warrior clan was amongst the hereditary vassals of the Tokugawa family (the fudai

Fudai

was a class of daimyo who were hereditary vassals of the Tokugawa in Edo period Japan. It was primarily the fudai who filled the ranks of the Tokugawa administration.-Origins:...

) in the Edo period

Edo period

The , or , is a division of Japanese history which was ruled by the shoguns of the Tokugawa family, running from 1603 to 1868. The political entity of this period was the Tokugawa shogunate....

Masatsuna was a polymath

Polymath

A polymath is a person whose expertise spans a significant number of different subject areas. In less formal terms, a polymath may simply be someone who is very knowledgeable...

 and a keen student of whatever information was available at that time concerning the West. Since most printed material was only available in the Dutch language, such studies were commonly called "Dutch learning" (rangaku

Rangaku

Rangaku is a body of knowledge developed by Japan through its contacts with the Dutch enclave of Dejima, which allowed Japan to keep abreast of Western technology and medicine in the period when the country was closed to foreigners, 1641–1853, because of the Tokugawa shogunate’s policy of national...

).

Dutch Japanologist Isaac Titsingh

Isaac Titsingh

Isaac Titsingh FRS was a Dutch surgeon, scholar, merchant-trader and ambassador.During a long career in East Asia, Titsingh was a senior official of the Dutch East India Company . He represented the European trading company in exclusive official contact with Tokugawa Japan...

 considered Masatsuna to have been his closest friend while he was in Japan, and their correspondence continued after Titsingh last left Dejima

Dejima

was a small fan-shaped artificial island built in the bay of Nagasaki in 1634. This island, which was formed by digging a canal through a small peninsula, remained as the single place of direct trade and exchange between Japan and the outside world during the Edo period. Dejima was built to...

 for the last time. The oldest surviving letter from Masatsuna to Titsingh dates from 1789; and this letter mentions mutual friends such as Shimazu Shigehide (the father-in-law of the eleventh shogun, Tokugawa Ienari

Tokugawa Ienari

Tokugawa Ienari; 徳川 家斉 was the eleventh and longest serving shogun of the Tokugawa shogunate of Japan who held office from 1787 to 1837.-First wife:...

) and Kuze Hirotami

Kuze Hirotami

, also known as ', was a late-18th century Nagasaki bugyō or governor of Nagasaki port, located on southwestern shore of Kyūshū island in the Japanese archipelago. Kuze was one of the Nagasaki bugyō between 1775 and 1784....

 (Nagasaki bugyō

Nagasaki bugyo

were officials of the Tokugawa shogunate in Edo period Japan. Appointments to this prominent office were usually fudai daimyō, but this was amongst the senior administrative posts open to those who were not daimyō...

or governor of Nagasaki port).

Masatsuna and Titsingh shared an interest in numismatics

Numismatics

Numismatics is the study or collection of currency, including coins, tokens, paper money, and related objects. While numismatists are often characterized as students or collectors of coins, the discipline also includes the broader study of money and other payment media used to resolve debts and the...

. After Titinsgh was reassigned from Japan in 1784, he sent packages of coins from India—Dutch coppers, as well as coins from India, Russia, Turkey, and Africa. Titsingh in turn received Japanese and Chinese coins as gifts.

Masatsuna was an author of several treatises on numismatics. He was the first in Japan to circulate a book about non-Japanese coins with impressions taken from actual coins which had been obtained from Western traders.

Events of a daimyo's life

• 1781 (Tenmei
  Tenmei
  was a Japanese era name , also known as Temmei, after An'ei and before Kansei. This period spanned the years from April 1781 through January 1789. The reigning emperor was .-Change of era:...
  
   1): This numismatist scholar's book, Shinzen zenpu ("Newly selected manual of numismatics"), was published.
• 1782 (Tenmei 2): This numismatist scholar's analysis of copper currency in China and Japan "Shinzen zenpu" was presented to the emperor.
• 1785 (Tenmei 5): This numismatist scholar's book, Kaisei kōhō zukan ("Corrected Illustrated mirror of coinage"), was published.
• 1785 (Tenmei 5): Masatsuna inherited his father's position and titles.
• 1787 (Tenmei 7): This rangaku/numismatist scholar's book, Seiyō senpu (Notes on Western Coinage), with plates showing European and colonial currency, was completed. -- see online image of 2 adjacent pages from library collection of Kyoto University of Foreign Studies and Kyoto Junior College of Foreign Languages

• 1789 (Kansei
  Kansei
  was a after Tenmei and before Kyōwa. This period spanned the years from January 1789 through February 1801. The reigning emperor was .-Change of era:...
  
   1): This rangaku/geographer scholar's book, Taisei yochi zusetsu ("Illustrated explanation of Western geography"), was published.
• 1800 (Kansei 11): Masatsuna retires, handing over his position and titles to his son, Mototsuna.
• 1801 (Kansei 12): Mototsuna predeceased his father, and Masatsuna's grandson, Tsunagata becomes daimyo.
• 1802 (Kansei 13): Masatsuna dies.

• 1807 (Bunka
  Bunka
  was a after Kyōwa and before Bunsei. The period spanned the years from January 1804 to April 1818. The reigning emperors were and .-Change of era:...
  
   4): Isaac Titsingh sends his last letter to Masatsuna from Europe, not knowing that his old friend had died some years earlier. Titsingh's decided to dedicate his translation of Nihon Ōdai Ichiran
  Nihon Odai Ichiran
  is a 17th century chronicle of the serial reigns of Japanese emperors with brief notes about some of the noteworthy events or other happenings.According to the 1871 edition of the American Cyclopaedia, the translation of Nihon Ōdai Ichiran in 1834 was one of very few books about Japan; and it was...
  
   to Masatsuna.

Selected work

Kutsuki's published writings encompass 8 works in 12 publications in 1 language and 25 library holdings.

• 1781 --
• 1785 -- ; note that only one copy known to exist.
• 1787 -- , also romanized as Seiyō senpu
• 1789 -- .
• 1790 —

Further reading

• The private correspondence of Kutsuki Masatsuna and Isaac Titsingh, 1785-1807: compiled in celebration of the friendship between Kutsuki Masatsuna and Isaac Titsingh, Fukuchiyama, November 1992. OCLC 069107485