100 Rupiah

The 1957 series was issued during a period of acute political instability in Indonesia — regional rebellions, including the PRRI-Permesta uprising that erupted in 1958, disrupted normal banking activity across much of Sumatra and Sulawesi. Notes of this period circulated unevenly, with some regions effectively cut off from central bank supply channels for months at a time.

Thomas De La Rue's involvement here reflects Bank Indonesia's continued reliance on established Commonwealth printers well into the late 1950s, before domestic printing infrastructure matured. The watermark remains the sole security feature — modest by any reckoning for a denomination of this value.