In 1901, in view of the strategic position of Penghu Island in the Taiwan Strait, the Japanese government announced on 2 July that Penghu was to be a "fortress". The "Penghu Fortress Command" was established thereafter.[4]
On 7 July 1937 the Marco Polo Bridge incident broke out, beginning the Second Sino-Japanese War. On 15 August, all of Japanese-controlled Taiwan entered into a war economy. In June 1939, the Japanese army used Penghu as an advance base to attack Mainland China from Shantou, Guangdong.[4]
Since 1943, the situation in the Pacific War has become increasingly dire for the Japanese. In view of the barren land and large population in Penghu, it became difficult for the Japanese to supply grain by sea, leading to a real risk of food shortage. Residents were evacuated to Formosa and special liaison officers were stationed in Budai, Tainan Prefecture, and Takao Prefecture.
In the early days Japan chose Magong as the site for the construction of a major naval headquarters, and forced the residents to relocate to other places. In 1901, the Magong Port Department was formally established. In 1929, Japan once again expropriated the land around Mount Daian on the opposite bank for the construction of fuel tanks. In 1941, the Magong Yao Port Department was upgraded to the Magong Garrison Office. In 1943, the command center of the Garrison Office was moved to Kaohsiung's Zuoying district. In addition to auxiliary support facilities such as radio stations, port warehouses, and oil tanks, the hinterland of the base also became the main strategic target for the Allied fighters to attack Penghu.[3]
After the Magong air raid on 14 March 1945, the offices in various parts of Penghu were dispersed. Except for a few civil servants who stayed behind in Magong, most of the residents of Magong street went to the suburbs. At that time, Magong Street was in ruins with few people. It was not until the end of World War II that it gradually restored its original appearance.