Pre-World War II
Kosaka town was a major industrial center during the Meiji period through the production of silver, copper, iron, and various other ores. During the early 1900′s, Kosaka was the highest producer of silver in Japan and an industrial and technological center during World War II. Due to Kosaka’s mining importance and thriving mining industry, the residents were some of the first in Japan to enjoy the luxuries of electricity and plumbing.
Post-World War II
The end of World War II led to a decrease in ore demand; combined with an increase in international trade, Japan’s mining industry went into a recession. Without another industry to fall back on, Kosaka struggled. The ensuing years saw Kosaka’s population decrease by over 50% (Est. 20,000 people in 1940 to est. 7,000 by the year 2000) and the population continues to shrink today. Kosaka’s last mine ceased operation in 1990, which has been converted into a recycling plant.