The Shortest Regency — Only Ten Days
Sadaaki was appointed 15th regent in 1326 but resigned after just ten days—the shortest regency in Hojo history. Amid intensifying internal power struggles and the domineering behavior of Nagasaki Takasuke, he is said to have resigned rather than endure the emptiness of a powerless office.
Guardian of Kanazawa Bunko
Sadaaki assiduously collected books and documents for Shomyo-ji and Kanazawa Bunko, nurturing one of medieval Japan's premier cultural centers. His collection ranged from Japanese and Chinese classics to Buddhist texts and documents, building the intellectual foundation of warrior culture. Even after the Kamakura shogunate fell, his collection survived and is now displayed as the Kanagawa Prefectural Kanazawa Bunko.