Original sentence: The fourth son of shogun Ashikaga Takauji, he was the first of a dynasty of five Kantō Kubō,  Kamakura-based  representatives in the vital Kantō region of Kyoto's Ashikaga regime
Edited sentence: The fourth son of shogun Ashikaga Takauji, he was the first of a dynasty of five Kantō Kubō,  Kamakura-based  representatives in the vital Kamakura-fu of Kyoto's Ashikaga regime