These were replaced by two twin 25mm guns in 1940. "Yūbari" had a significant refit in early 1944 when the two single /50 main guns were removed and replaced by one Type 10 /45 gun (in the "A" position) and six twin and one triple Type 96 25-mm AA guns together with a Type 22 search radar and two depth charge launchers. "Yūbari" was laid down on 5 June 1922, launched on 5 March 1923 and completed at Sasebo Naval Arsenal, and commissioned on 23 July 1923. Completed just prior to the 1923 Great Kantō earthquake, "Yūbari" was quickly pressed into service to help evacuate refugees from Yokohama and other stricken areas. During this time (10 September 1923), Crown Prince Hirohito also visited the vessel while at Yokosuka. In April 1925, "Yūbari" shadowed maneuvers of the United States Navy off of Oahu. American destroyers gave chase, but "Yūbari" was able to outrun them. She was reassigned to the reserves in November 1933. In November 1934, Captain Tadashige Daigo assumed command, and "Yūbari" was reassigned to the Yokosuka Naval District, where she was modernized and refitted in November 1935. Afterwards, she was assigned to patrols off of the China coast. With the start of the Second Sino-Japanese War in August 1937, "Yūbari" assisted in the evacuation of Japanese civilians from coastal cities in southern China. Subsequently, she was sent north to cover landings by the Imperial Japanese Army at Hangzhou on 20 October. She returned to Yokosuka and was reassigned to the reserves in December of the same year. She was sent from March through October 1939 to the Ōminato Guard District to patrol the coast of Sakhalin . At the time of the attack on Pearl Harbor, "Yūbari" was flagship of Destroyer Squadron Six of the IJN 4th Fleet, tasked with the defense of the South Pacific Mandate, and was based out of Truk from late 1941 through 1942. Early in the war, "Yūbari" was the flagship for the Japanese invasion force during the invasion of Wake Island. She led both invasion attempts on 11 and 23 December 1941. During shore bombardment operations, she was bracketed by gunfire from the USMC defenders, but took no damage. Subsequently, "Yūbari" and her destroyers participated in the capture of Rabaul and New Ireland in the Solomon Islands, followed by the Invasion of Salamaua–Lae on 8 March 1942.