30-07-2025
Researcher seeks to save Osaka Army Arsenal as 'negative legacy'
A military factory that was said to be the largest in the Orient was once in operation at a site now part of Osaka Castle Park at the center of the city of Osaka, and a researcher is calling for the remaining buildings to be preserved as a "negative legacy."
Osaka Army Arsenal, which manufactured artillery for the now-defunct Imperial Japanese Army, employed up to around 66,000 people, including mobilized students, across its approximately 6-million-square-meter site.
Osaka Castle Park is lush with greenery and bustles daily with people enjoying jogging, as well as visitors from abroad. Next to Osaka Castle Hall in the park is a commemorative monument with an inscription reading "Army Arsenal site" and an explanatory plaque, but few people stop to look at it. A man who was out cycling said, "I vaguely knew the factory existed, but I didn't realize it was that big."
According to Koji Miyake, professor emeritus at Mukogawa Women's University who specializes in the history of science and technology, Osaka Army Arsenal was set up in 1870 at the suggestion of Masujiro Omura, who played an active role in the establishment of the Imperial Japanese Army. The latest metalworking technologies of that time were introduced, and military trucks and tank engines were also produced.
On Aug. 14, 1945, the day before the radio broadcast by then-Emperor Hirohito announcing Japan's surrender in World War II, the arsenal was targeted by U.S. air raids. More than 80% of it was destroyed, rendering the complex inoperable, according to the office of Osaka's Chuo Ward.
Koji Miyake, professor emeritus at Mukogawa Women's University, speaks in May in front of a commemorative monument with an inscription reading "Army Arsenal site" in the city of Osaka. |
Jiji
After the war, Osaka Castle Park and other facilities were built on the site of the arsenal, and only a few buildings remain, such as the chemical analysis laboratory where weapons research and development were conducted. The brick building of the laboratory was used as a classroom building by the University of Osaka, but is now closed to the public due to the risk of collapse.
With the country marking the 80th anniversary of its surrender in the war next month, there are few people left who can recount their memories of the arsenal. Neither the national nor municipal governments that own the factory site are actively seeking to utilize the ruins.
"The weapons manufactured at the arsenal were used in a war of aggression," Miyake said. "It is necessary to continue to preserve the ruins appropriately as a negative legacy so that war will never happen again."
