was a daimyō

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...

 in late-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....

 Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

, who ruled Yokosuka Domain

Yokosuka Domain

' was a Japanese feudal domain of the Edo period, located in Tōtōmi Province. Yokosuka was a Fudai domain. It was centered at Yokosuka Castle in the Matsuo district of the city of Kakegawa in Shizuoka Prefecture.-History:...

 in Tōtōmi Province

Totomi Province

was a province of Japan in the area of Japan that is today western Shizuoka Prefecture. Tōtōmi bordered on Mikawa, Suruga and Shinano Provinces. Its abbreviated form name was .-History:...

.

Tadasaka was the second son of Sakai Tadazane, daimyō of Himeji Domain

Himeji Domain

The ' was a Japanese domain of the Edo Period, located in Harima Province .-List of lords:*Ikeda clan #Terumasa#Toshitaka#Mitsumasa*Honda clan #Tadamasa#Masatomo#Masakatsu...

, and was adopted by the heirless 6th daimyō of Yokosuka Domain, Nishio Tadakata

Nishio Tadakata

was a daimyō in late-Edo period Japan, who ruled Yokosuka Domain in Tōtōmi Province.Tadakata was the fourth son of Nishio Tadayoshi, and succeeded his father as head of the Nishio clan and daimyō of Yokosuka in 1829. HIs wife was a daughter of Matsudaira Muneakira, daimyō of Miyazu Domain in Tango...

, to be his successor. When Tadakata retired from public life in 1843, Tadasaka became daimyō and head of the Nishio clan

Nishio clan

The was a Japanese clan claiming descent from the Kira clan, a branch of the Seiwa Genji line. Kira Yoshitsugu, a son of Kira Mochihiro, served under Oda Nobunaga, Toyotomi Hideyoshi and Tokugawa Ieyasu adopted the family name of Nishio...

.

Tadasaka entered into the administration of the Tokugawa shogunate

Tokugawa shogunate

The Tokugawa shogunate, also known as the and the , was a feudal regime of Japan established by Tokugawa Ieyasu and ruled by the shoguns of the Tokugawa family. This period is known as the Edo period and gets its name from the capital city, Edo, which is now called Tokyo, after the name was...

 in 1846, as a Sōshaban

Sōshaban

were officials of the Tokugawa shogunate in Edo period Japan. Conventional interpretations have construed this Japanese title as "master of ceremonies."...

(Master of Ceremonies). With regards to the administration of his own domain, he helped place its finances on a more stable footing by encouraging the cultivation of green tea

Green tea

Green tea is made solely from the leaves of Camellia sinensis that have undergone minimal oxidation during processing. Green tea originates from China and has become associated with many cultures throughout Asia. It has recently become more widespread in the West, where black tea is traditionally...

 and the increased production of lumber. Tadasaka, like several of his predecessors, was skilled in the arts. he had the nom de plume of .

Tadasaka died on August 26, 1861, at the Nishio clan residence in Soto-Sakurada, Edo

Edo

, also romanized as Yedo or Yeddo, is the former name of the Japanese capital Tokyo, and was the seat of power for the Tokugawa shogunate which ruled Japan from 1603 to 1868...

, at age 40. His grave is located at the Nishio clan temple of Ryumin-ji in what is now part of the city of Kakegawa, Shizuoka

Kakegawa, Shizuoka

is a city in western Shizuoka Prefecture, Japan. As of 2010, the city had an estimated population of 117,858 and a population density of 444 persons per km². The total area was 265.63 km².-Geography:...

. He was succeeded by his son Tadaatsu

Nishio Tadaatsu

Viscount was the final daimyō of Yokosuka Domain in Tōtōmi Province in late-Edo period Japan, and the first daimyō of Hanabusa Domain in Awa Province in the early years of the Meiji period....

.