The town of
Obock, in the Gulf of Aden near the red sea, was occupied by the French in 1883. French Colonies general issue stamps were put into use then, and replaced by Obock stamps in 1892.
In 1893, the French moved there administration headquarters to
Djibouti, just to the south across the Gulf of Tadjoura. Stamps were issued for Djibouti (overprints on Obock), but Obock regular stamps were also valid there.
The territory had gradually expanded inland, and the name was changed to
Somali Coast Protectorate, with stamps issued under that name in 1994. These stamps also have the inscription "Djibouti 1893-94". That I don't know why. Were they commemorating the move to Djibouti?
In 1902, the name was again changed, with stamps issued under
French Somali Coast.
In 1967, the name was changed to
Afars and Issas, and stamps were issued in the same year.
In 1977, Afars and Issas became the independent
Republic of Djibouti, again issuing new stamps under that name.
In their own pathetic way, Scott Catalogue spreads this area all over the place.
Obock has it's own listing under "O". The move to Djibouti is listed with the issues inscribed French Somali Coast under "S". Now why isn't Obock included there? And why not under "F" like French West Africa or French Congo? Afars and Issas are under "A", while the independence name change to Djibouti is under "D". Yikes.
Here is a nice used example I have of French Somali Coast No. 15, with a 1902 Djibouti cancel in blue.

