At the turn of the 19th to the 20st century, during and after the German colonial era in the northern part of what is today Papua New Guinea, the only creole language in the world based on German arose among children of mixed background (German and other non-indigenous fathers and indigenous mothers) at the Missonaries of the Sacred Heart Catholic mission school in Vunapope in what is today East New Britain, Province, then Neupommern: Unserdeutsch, or Rabaul Creole German, as it is also called in the research literature.

In many respects, Unserdeutsch has an exceptional position among the world's creole languages and, of course, it is of particular importance for Germanic linguistics.

Unserdeutsch will soon be extinct. In 2015, there are only about 100 speakers left. The vast majority are more than 70 years old. Most of them now live in eastern Australia in and around Brisbane and Sydney. Only a small remnant of the once closed language community is still living in Papua New Guinea, scattered over various islands of the Bismarck Archipelago.

A short television broadcast about Unserdeutsch by SBS World News is available here.