In 1907, rich deposits of phosphates were discovered on the island of Angaur in the Palau Island chain of the western Carolines. The Deutsche Südsee-Phosphate Aktien Gesellschaft (German South Sea Phosphate Company soon began mining operations, and the Reichspost opened a post office on Angaur on 18 February 1909 to service the local German population.

This cancel is also known of stamps of Marshall-Inseln from March to June 1910. These stamps were presumably brought to Angaur by ships and personnel of the Deutsche Südsee-Phosphate Aktien Gesellschaft prior to the opening of a post office on Angaur, and were used sporadically in 1910 despite there being no reported lack of Karolinen postage.

The last known mail departure from Angaur was in early August 1914. Angaur was occupied by Japanese forces on 12 October 1914, forcing the closure of the German post office.