20 Rupien

By 1915, the naval blockade had made it impossible for the Deutsch-Ostafrikanische Bank to import professionally printed notes from Germany. These 20 Rupien emergency issues were produced locally in Dar es Salaam on whatever materials were at hand — hence the cardboard stock, which varies noticeably in weight and tint across surviving examples. Lettow-Vorbeck's campaign kept German East Africa fighting longer than any other colonial theater, and the currency had to keep pace with it.

The cardboard substrate makes these unusually vulnerable to delamination along the edges, a condition issue specific to the 1915 emergency series rather than a function of handling.