Void Century

Also referred to as the Blank Century, this is the period 800 years ago when a great civilization dominated the world and then at the end of the century they disappeared. At the end of the century the World Government came to power and censored everything that happened in the previous 100 years.

This period became known as the blank century because there is nothing left to acknowledge anything that happened, aside from the Poneglyphs which are written in a language that few know how to read. However, it causes a problem with the known histories of the world as nothing ties up because of that missing period, although most people do not seem to know about this information. For example Nefertari Cobra after told by Nico Robin about this missing period was completely shocked by its existence and didn't know there were parts of the world history that didn't tie in.

For the World Government, the events of this period are better left unknown as information linked to it is considered far too dangerous.