Letter from Mogami Yoshiaki, addressed to Nishino Michitoshi

November 24th 1587 (Tenshō 15)

Tangible Cultural Property, designated by Sakata city

Donated by the Homma family

This is a letter from Mogami Yoshiaki(1546–1614), a daimyō of the Yamagata Domain in Dewa Province, informing Nishino Michitoshi, a vassal of Onodera Yoshimichi of Yokote (in present-day Akita Prefecture) of his decision to pacify the Shōnai district. 

After the death of Mutō Yoshiuji (Daihōji) (1551–83), the feudal lord of the Shōnai district and the 17th head of the Daihōji clan, his younger brother Yoshioki regained power with assistance from Uesugi Kagekatsu. However, in 1587, Mogami Yoshiaki led major forces to expand his territory in the Shōnai area. 

In this letter, Yoshiaki also expresses his gratitude towards the Onodera clan for their gift of a horse as a celebration of his conquest of Shōnai; and states that the Rokugō clan should be forgiven for their crimes, noting that arrangements should be made to ensure their usefulness in future. The letter illuminates the relationship between Yoshiaki and the Senboku region, as well as some of his political personnel. 

Note: In a samurai or aristocratic household, 修理 Shuri refers to “head of repairs and constructions” in pre-modern Japan – someone who was responsible for upkeep and repairs. 修理の亮 Shuri no suke is the undersecretary of such, seen in the Japanese title of this letter.