These are documents related to the Fukao Household who were the chief Karo (high ranking warriors who oversaw the feudal lord's work) for the Sakawa feudal lords in the Edo era.
Although the collection does not contain many documents, they are a valuable clue for learning about the Fukao Household and Sakawa at that time.

This collection is the core of the current Seizan Bunko and comprises of around 13,000 volumes donated by Mitsuaki Tanaka, the former minister to the imperial household,
who was sympathetic towards the activities of Kawada Bunko. It also includes a collection of writings by the political activists around the time of the Meiji restoration,
as well as documents related to the Imperial Household, donated by Mitsuaki and his descendants.

This is the collection of books belonging to Taizo Nishitani, who was born in Sakawa Town, and devoted his life to the research and translation of "The Natural History and Antiquities of Selborne".
The total number of works in Japanese and English combined totals almost 10,000,
and his collection includes many rare works such as "The Natural History and Antiquities of Selborne"the subject of his research, "Anatomical Tables" a book on anatomy written by a German doctor, and the first Japanese translation of Darwin's "Origin of the Species".