German post offices in the Ottoman Empire

[2] On March 1, 1870, the Norddeutscher Postbezirk (i.e. the postal service of the North German Confederation) opened its first office in Constantinople (Istanbul) using definitive stamps without overprint.

After January 1872, the Reichspost took over the management of the office and expanded it further as "Deutsche Post in der Türkei".

The overprint did not include an additional country name, as was the case with stamps issued for use at the German post offices in Morocco and China.

[4] Beginning in 1908, the German Post Offices in Turkey issued an additional set of stamps which it sold at the same time as the series overprinted with values in Turkish piasters.

For whatever reason, accepting French francs in exchange for stamps apparently made the German Parcel Post rates more competitive once more.