I stumbled upon these vintage travel posters link and found only three posters about Indonesia. The posters were made between 1920 and 1940, when the country's official name was Dutch East Indies, still under the Dutch colonial regime and the eastern part of Indonesia (Maluku and Papua) was under the Portuguese colonial regime.
I wonder what kind of vehicle that would take 36 hours to travel from Singapore to Java. I have taken the trip from Java to Singapore by ship. It was 3x24 hours. Thank God for airplanes! Source
The map excluded the current Indonesia's eastern islands, such as Maluku and Papua. Source
Bali has always been the tourism attraction. Source