In November 1897, two German missionaries were murdered by a mob in Kiautschou. German naval forces occupied the city, and the German government used the occupation to press the Chinese government for a long-term lease of the port. In March 1898, Germany and China entered into a 99-year lease under which Germany would control both sides of the entrance to Kiautschou Bay, as well as the islands within. Around this leased territory would be a small neutral zone which would, in effect, also be under German control.
Tsangkou was a station on the Shantung Railway connecting Tsingtau, Kiautschou, with Tsinan, China.
A postal agency was opened at Tsangkou on 1 April 1901. On 6 December 1904, the postal agency was redesignated an auxiliary postal agency, and the official canceller was removed from service.
The station remained an auxiliary postal agency until being once again designated an official postal agency on 1 May 1913. During the auxiliary period, a supplemental handstamp was used to mark mail sent from Tsangkou, but a subseqent cancellation, usually from Tsingtau, was required to cancel postage.
The Tsangkou postal agency remained open until the early days of World War I, closing in mid-September 1914.