British invasion of French Somaliland

French Somaliland (officially the Côte française des Somalis, "French Somali Coast"), with its capital at Djibouti, was the scene of only minor skirmishing during World War II, principally between June and July 1940. After the fall of France (25 June 1940) the colony was briefly in limbo until a governor loyal to the Vichy government was installed on 25 July. It was the last French possession in Africa to remain loyal to Vichy, surrendering to Free French forces only on 26 December 1942. Pierre Nouailhetas governed the territory through most of the Vichy period. In response to aerial bombardment by the British, he instituted a brutal reign of terror against both Europeans and locals, and was eventually recalled and forced to retire. From September 1940, the colony was under an Allied blockade, and many of its inhabitants fled to neighbouring British Somaliland. After the territory's liberation, it cycled through governors rapidly and recovery from the deprivation of 1940–42 was only beginning when the war ended in 1945.

In 1934–35, Italo-Ethiopian tensions were affecting the Horn of Africa while in Europe German re-armament weighed on the French government. Looking for Italian support against Germany in the event of war, France ceded several territories, including a small piece of territory in northern Somaliland to Italian Eritrea, in the Mussolini–Laval Accord of 7 January 1935. This treaty was never ratified by Italy and although preparations were made to transfer the territory, it was not actually transferred prior to the outbreak of war in 1940.

In 1935, Italy invaded Ethiopia and the French government paid increased attention to the defence of French Somaliland. In January 1938 an Italian force moved down onto the plain of Hanlé in French territory and encamped there. Italy claimed that this territory lay on the Ethiopian side of the border, as per the Franco-Ethiopian treaty of 1897. The French colonial minister, Georges Mandel, and the commander-in-chief at Djibouti, Paul Legentilhomme, responded by strengthening the colony's defences to unprecedented levels: 15,000 troops were stationed there and posts were established at Afambo, Moussa Ali and even on the other side of the Italians. The landward fortifications were augmented extensively with concrete.

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