Following Spain’s 1898 defeat in the Spanish-American War, it sold its remaining Pacific possessions, including the Mariana Islands, to Germany.

On 18 June 1899, the German government declared Marianen to be a German colony, with its headquarters at Garapan on the island of Saipan.  The post office on Saipan was the only official post office in Marianen.

From December 1900 to March 1903, Saipan was without regular mail steamer service.  As a result, mail was loaded onto any passing vessel, civilian or military, that could transport it to a port of call that had regular mail service.  One of these ports was Agana in the nearby U.S. possession of Guam.  On occasion, this mail arrived in Agana without being cancelled, so in Agana a handstamped “AGANA, GUAM” was applied to cancel the postage.