In 1370, Imagawa Sadayo (Ryoshun) was appointed by the "kanrei" Yoriyuki and the Senior Vassal Council to bring down the last bastion of Southern Court resistance in Kyūshū. After a grueling twelve-year campaign, imperialist resistance collapsed with the defeat of the Kikuchi clan in 1381; and with the death of Shimazu Ujihisa in 1385, the last Kyūshū provincial domain declared its allegiance to the regime. With the fall of Kyūshū the whole of western Japan came under the rule of the Ashikaga regime. However, campaigns alone were inadequate to legitimize Ashikaga rule over the nobles.