During the Second World War, Italian East Africa was occupied by a British-led force including colonial units and Ethiopian guerrillas in November 1941.

Some Italian historians such as Franco Catalano and Giorgio Rochat argue that the invasion was an act of social imperialism, contending that the Great Depression had badly damaged dictator Benito Mussolini's prestige, and that he needed a foreign war to distract public opinion.

[7] Other historians such as Pietro Pastorelli have argued that the invasion was launched as part of an expansionist program to make Italy the main power in the Red Sea area and the Middle East.

Italian belligerence also closed the Mediterranean to Allied merchant ships and endangered British supply routes along the coast of East Africa, the Gulf of Aden, Red Sea and the Suez Canal.

[12] In January 1942, with the final official surrender of the Italians, the British signed an interim Anglo-Ethiopian Agreement with Selassie, acknowledging Ethiopian sovereignty.

In November 1949, the United Nations granted Italy trusteeship of Italian Somaliland under close supervision, on condition that Somalia achieve independence within ten years.

The new titulature of the Italian king, originally accepted only by some countries politically aligned with Fascist Italy such as Nazi Germany and Imperial Japan, was recognized by forty-seven states by November 1938.

[18]: 5 Italy's Fascist regime encouraged Italian peasants to colonize Ethiopia by setting up farms and small manufacturing businesses.

[18]: 6  Continued insurgency by native Ethiopians, lack of natural resources, rough terrain, and uncertainty of political and military conditions discouraged development and settlement in the countryside.

The route was enlarged to 6,379 km and initially joined Rome with Addis Ababa via Syracuse, Benghazi, Cairo, Wadi Halfa, Khartoum, Kassala, Asmara, Dire Dawa.

The most important railway line in the African colonies of the Kingdom of Italy, the 784 km long Djibouti-Addis Ababa, was acquired following the conquest of the Ethiopian Empire by the Italians in 1936.

In 1938 following the Italian conquest, train speed was increased with the introduction of four high capacity railcars "type 038" derived from the model Fiat ALn56.

[25] However Ethiopia and Africa Orientale Italiana (AOI) proved to be extremely expensive to maintain, as the budget for the fiscal year 1936-37 had been set at 19.136 billion lira to create the necessary infrastructure for the colony.

[18]: 5 The architects of the Fascist regime had drafted grandiose urbanistic projects for the enlargement of Addis Ababa, in order to build a state-of-the-art capital of the Africa Orientale Italiana, but these architectural plans -like all the other developments- were stopped by World War II.

Andrea Festa, who was made director of the central office governing primary education in Eritrea in November 1932, declared in 1934 that Fascist efforts in education needed to ensure that native Africans were "acquainted with a little of our civilisation" and that they needed to "know Italy, its glories, and ancient history, in order to, become a conscious militia man in the shade of our flag."

Their propagandistic nature was especially apparent in history textbooks issued to African children, which entirely omitted any discussion of events such as Italian disunity, Giuseppe Mazzini's "Young Italy" movement, the revolutions of 1848, or Giuseppe Garibaldi's Expedition of the Thousand and instead stressed the "glories" of the Roman Empire and those of the Italian state that claimed to be its successor.

Use of the Fascist salute was mandatory in schools for African children, who were constantly encouraged to become "little soldiers of the Duce", and every day there was morning ceremony at which the Italian flag was hoisted and patriotic songs were sung.

During World War II, which saw the liberation of Italian East Africa from Fascism, few Africans displayed any loyalty to the Fascist state that the state's schools had so fervently tried to instill, and Ethiopia post-World War II found itself impoverished of skilled workers due to the very limited and propagandistic education provided to its non-Italian inhabitants under Mussolini's rule.

[31] He was subsequently removed by Mussolini and replaced by Prince Amedeo, Duke of Aosta, who followed a more conciliatory policy towards the natives, obtaining a huge success in pacifying Ethiopia.

[34][citation needed] Main colonial governors: Agenore Frangipani; Guglielmo Nasi; Enrico Cerulli; Pietro Gazzera; Luigi Frusci; Alessandro Pirzio Biroli