1 Sen

The Taiwan Government-General (Taiwan Sōtokufu) issued fractional currency in the late Meiji and Taishō periods largely to address the chronic small-change shortages that plagued colonial commerce. Copper coin production lagged well behind the pace of economic development the Japanese administration was deliberately forcing on the island, and paper sen notes filled the gap in a way that metal coinage simply couldn't keep up with.

The 1918 dating places this squarely in the middle of World War One, when global metal supplies were under severe pressure and Japanese mint priorities lay elsewhere.