Saipan on 23 June, stopped at Eniwetok and Tarawa to pick up Army troops and Japanese prisoners, and continued on to Pearl Harbor where she arrived on 9 July. After disembarking her passengers, she began the first of two voyages between San Diego and Hilo, Hawaii, carrying troops and equipment between the two points. At the end of these shuttle runs, the transport sailed for the Admiralty Islands. She arrived at Manus on 3 October and began preparations for the long-awaited operations to liberate the Philippine Islands. On 14 October, Arthur Middleton sortied with TG 79.2 and arrived in Leyte Gulf on the 20th. The ship remained in the area unloading troops until 24 October, when she headed for Hollandia, New Guinea. The attack transport returned to Leyte on 14 November, carrying personnel and supplies from Hollandia and Morotai, Netherlands East Indies. The next day, she sailed back to New Guinea and conducted training exercises in conjunction with Marine Corps units. On 31 December, the ship sailed with TG 79.4 for the invasion of Luzon and arrived in the transport area in the Lingayen Gulf on 9 January 1945 and landed her troops in the face of enemy air attack. During the operation, fifteen members of her crew were wounded by flying shrapnel from the guns of other vessels firing at the Japanese planes. The transport left Lingayen Gulf later that day to take on more supplies at Leyte and returned to Lingayen Gulf on 27 January. During February and early March, Arthur Middleton carried out training exercises at Guadalcanal. On 16 March, the transport sailed with TG 53.1 for Ulithi, where staging operations were held for the Ryūkyū campaign. The ship discharged troops and cargo at Okinawa during the first five days of April and then returned via Saipan to Pearl Harbor. She was routed on to the west coast and arrived at San Pedro, Calif., on 30 April to begin a period of overhaul. While the ship was still in the yard, Japan surrendered on 14 August 1945. The repair work was completed on 4 September, and Arthur Middleton was assigned to duty transporting relief forces to the Philippines and returning veterans to the United States. By the end of 1945, the ship had made two voyages to the Philippines. In January 1946, she underwent repairs at Terminal Island, California. Following the detachment of her Coast Guard personnel,