In the mid-1870’s, German companies established the first trading ties within the area that would become German New Guinea.  In 1884, the German flag was raised over several coastal towns, and the Neu Guinea Kompagnie was chartered to administer the area in 1885.  This included the ability to administer postal services.

On 1 April 1899, the German government assumed responsibility for administering the colony, citing the inability of private sources to finance the necessary development within the colony.

A post office was opened at Namatanai on 11 January 1911.  It would remain open until Australian forces occupied Namatanai in November 1914.

When the post office at Namatanai opened on 11 September 1911, there was no canceller present.  The round Namatanai canceller shown below was not dispatched from Bremen until 30 August 1911, arriving on an unknown date in November or December 1911.

The question of what was used to cancel mail in the period from 11 September 1911 until the canceller arrived has never been conclusively answered.  However, several stamps exist with manuscript cancels from that period. 

According to an article by E.E. Schlieper in the September 1997 issue of Vorläufer, #108:17-20, four copies are known (a fifth copy is shown in the article, but is believe to be a forgery).

Three appear to be philatelic usages from a single cover, as they bear identical markings on the same date (items 1a., 1b., and 1c.).  The fourth copy (1d.), referred to by Schlieper as the Kilian copy after its owner at that time, bears a manuscript cancel of 7 October 1911, and a subsequent Rabaul cancel.  Of the four copies, this is the most likely to be genuine, as mail from Namatanai would have been routed to Rabaul, where a proper cancel could have been applied.

The manuscript cancels were written with ink containing iron using a steel pen.  The handwriting on the four copies appears to be the same, lending credence to the belief that they are legitimate contemporary usages.

Two of these copies (1a. & 1d.) are in the GermanStamps.net Collection.