Naomasa was born the 17th son of
Nabeshima Narinao, the 9th
daimyō of Saga Domain. His mother was a daughter of
Ikeda Harumichi. His wife was the 18th daughter of
shōgun Tokugawa Ienari, and one of his concubines was the 19th daughter of
Tokugawa Narimasa. On the retirement of his father in 1830, Naomasa was appointed 10th
daimyō of Saga at the age of 17. In celebration of his new role and to reinforce the close relations between the Saga domain and the shogunate, his father-in-law, Shōgun Tokugawa Ienari, allowed him the use of one character from his name. Thus, "Narimasa" (斉正) was written until the end of the
Edo period. Naomasa inherited a domain on the verge of bankruptcy due to high expenses associated with its role in guarding the foreign settlement at nearby
Dejima and due to the profligate spending habits of Naomasa’s father. When Naomasa was appointed
daimyō in
Edo and prepared to make a journey back to his domain, a mob of creditors besieged his Edo residence demanding repayment on outstanding debts before he departed the city. However, Naomasa’s attempts to reform domain finances were continually blocked by his retired father, whose conservative politics and resistance to innovation were at odds with any new policies he attempted to implement. Naomasa was only able to take full control after the 1835 fire at
Saga Castle. Using the need to raise funds to reconstruct the castle as a justification, he cut the number of
samurai supported by the Saga domain to one-fifth of its previous level and established a number of industries, including the production of weapons, charcoal, and tea as domain monopolies. At the same time, he made a strong investment in the domain academy, the to train future leaders of Saga Domain in the latest technologies. Through his contacts at nearby
Nagasaki, he imported
Armstrong cannon, far more powerful than anything deployed by the
Tokugawa shogunate to date, and had the weapons
reverse engineered with copies made by Saga armories. He built the first
reverberatory furnace in Japan and invited competent artisans, including swordsmiths and metal casters, from around Japan to migrate to Saga regardless of their social standing. He also sponsored the development of
steam engines and steam-powered warships. In 1853, with the arrival of
Commodore Matthew Perry to end Japan’s
national isolation policy, he was initially vocal in his support of the
Sonnō jōi faction, and assisted the Tokugawa government in building coastal defense batteries around
Edo Bay. However, he also secretly opened direct negotiations with Great Britain, and later emerged as a proponent of opening the country to foreign trade. He officially retired from the position of
daimyō in 1861. Even after retirement, he kept an active hand in the development of Saga Domain, strongly supporting
rangaku studies, especially in the fields of
western medicine, weaponry and military tactics. He introduced
smallpox vaccination into Japan, experimenting first on his own son. In the unsettled Bakumatsu period, Saga emerged as one of the militarily strongest of the Japanese domains, and Naomasa attempted to maintain a policy of neutrality between the moderate
Kōbu Gattai faction which wished to reconcile the Tokugawa shogunate with the
Imperial Court, and the more radical factions supporting either the Emperor or the Shōgun. During the
Boshin War of the
Meiji Restoration, he joined his forces with the
Satchō Alliance in support of
Emperor Meiji. After the
Battle of Toba–Fushimi he fought against the Tokugawa remnants at the
Battle of Ueno and in the various campaigns in northern Japan against the
Ōuetsu Reppan Dōmei. Naomasa was appointed a councilor to the new
Meiji government. With the
abolition of the han system, he surrendered his office and was appointed governor until Saga Domain was absorbed into the new
Saga Prefecture in July 1871. Together with
Shimazu Yoshitake, he was appointed Commissioner of Colonial Affairs, and tasked with the settlement of
Ezo and other lands in northern Japan. He died in 1871 at the Saga domain residence in Tokyo. Some of Naomasa's physical legacies include
Saga Castle, which is being actively renovated, and a reconstruction of his
Kakurin-tei (郭林亭) Japanese tea house located in the grounds of Kōno Park,
Saga City, Japan. The new museum at Saga Castle provides excellent information on Naomasa's life and accomplishments. ==References==