 Tsuneshige's son, (1118–1201) was instrumental in aiding Minamoto no Yoritomo (1147–1199) with the establishment of the Kamakura shogunate.Tsuneshige built a spacious residence and numerous temples in present-day Chiba City, and in the same period he transferred his power base from Ōji Castle to Inohana Castle on Mount Inohana.The area of present-day Chiba City became "jōkamachi" , or castle town, and prospered under the Chiba clan.