Sakai Tadamochi

Sakai Tadamochi (酒井 忠用, January 3, 1725 – October 21, 1775) was a Japanese daimyō of the mid-Edo period.

The Sakai were identified as one of the fudai or insider daimyō clans which were hereditary vassels or allies of the Tokugawa clan, in contrast with the tozama or outsider clans.

Tadamochi is part of a cadet branch of the Sakai which had been created in 1590.

The fudai Sakai clan originated in 14th century Mikawa Province. The Sakai claim descent from Minamoto Arichika. Arichika had two sons: one of them, Yasuchika, took the name Matsudaira; and the other son, Chikauji, took the name Sakai—and this samuari ancestor is the progenitor of this clan's name.

Sakai Hirochika, who was the son of Chikauji, had two sons, and their descendants gave rise to the two main branches of the Sakai clan. Hirochika's younger son, Sakai Masachika, served several Tokugawa clan leaders -- Nobutada, Kiyoyasu and Hirotada; and in 1561, Masachika was made master of Nishio Castle in Mikawa.

Sakai Sigetada, who was the son of Masachika, received the fief of Kawagoe Domain in Musashi Province in 1590; and then in 1601, Sigetada was transferred to Umayabashi Domain in Kōzuke Province.

Sakai Tadakatsu (1587–1662), who was Sigetada's son, was transferred in 1634 to Obama Domain in Wakasa Province where his descendants resided until the Meiji period. In a gesture demonstrating special favor to the Sakai, the second shogun, Hidetada, allowed the use of his personal Tada- in the name Tadakatsu.

The head of this clan line was ennobled as a "Count" in the Meiji period.

Tadamochi served the Tokugawa shogunate as its twenty-first Kyoto shoshidai in the period spanning May 20, 1752 through May 5, 1756.

In 1754, the earliest recorded post-mortem examination in Japan was supervised by Tadamochi's personal physician. This investigation by Kosugi Genteki (1730–1791) was considered highly controversial by his contemporary peers. The autopsy involved an examination of the corpse of an executed criminal somewhere within the precincts of Jidoin Temple north of Nijo Castle; and the results were eventually published in Zoshi (Description of the Organs) in 1759.

Tadamochi is buried with others of his clan at Kuniji in Obama in what is today Fukui Prefecture.