On June 4, 1859, the former French consular agent in Aden, Henri Lambert, was assassinated in the Gulf of Tadjourah.

[4] After an investigation by the French envoy Stanislas Russel, the commander of the naval station of the East Coast of Africa (based in Réunion Island), Viscount Alphonse Fleuriot de Langle, was tasked with arresting the presumed culprits.

On March 11, 1862, representatives of the sultan of Tadjourah (Diny Ahmed Aboubekr, Mohammed Hammed, and Aboubekr Ibrahim Chahim), who had come to Paris following this incident, concluded an agreement with Édouard Thouvenel, Foreign Minister of Napoleon III, by which they ceded to France “the ports, harbor, and anchorage of Obock located near Cape Ras Bir along with the plain extending from Ras Aly in the south to Ras Doumeira in the north”.

[6] On this occasion, the official takeover of Obock was made by Frigate Captain Buret of the Curieux, who noted in his report to the Minister of the Navy that he was convinced that if the inhabitants of this coast desired the French presence,it was because they were persuaded that we were indifferent to the slave trade and that we would allow their boats to fly the French flag to cover their illicit trade.

Due to the closure of the post office in Obock in 1894, the remaining stock of stamps was used until depleted in Djibouti.