The Kutsuki were a branch of the Sasaki family hailing from Omi Province. They served as the stewards of the Kutsuki manor in that province in the Kamakura period, and the house continued through the Warring States period and into the Edo period, when some of their members became bannermen (direct vassals of the shogun) or daimyo (provincial lords). "The archives of Kutsuki family" consist of historical documents passed down in the family through the years. The Cabinet Records Bureau purchased them from the Kutsuki in 1888. Containing more than 1,060 documents, the archives were designated an important cultural property in the first year of Heisei( 1989).
Shuinjo (red-sealed letter) of Toyotomi Hideyoshi to Kutsuki Mototsuna dated September 21 in the 3rd year of Bunroku (1594). In the letter, he was assigned as co-deputy with Shinjo Togyokusai (Naotada) to oversee the 57,878 koku terrritory directly governed by the Toyotomi family in Ano-gun of Ise Province (present day Mie Prefecture) and that he will be given 2000 koku from the territory. Letter was folded type.