In addition to conventional weaponry, Badoglio's troops also made substantial use of mustard gas, in both artillery and aerial bombardments. In total, the Italians deployed between 300 and 500 tonnes of mustard gas during the war, despite having signed the 1925 Geneva Protocol. The deployment of gas was not restricted to the battlefield, however, as civilians were also targeted by the Italians, as part of their attempt to terrorise the local population. Furthermore, the Italians carried out gas attacks on Red Cross camps and ambulances.[6]
The armed forces disposed of a vast arsenal of grenades and bombs loaded with mustard gas which were dropped from airplanes. This substance was also sprayed directly from above like an "insecticide" onto enemy combatants and villages. It was Mussolini himself who authorized the use of the weapons:
"Rome, 27 October '35. A.S.E. Graziani. The use of gas as an ultima ratio to overwhelm enemy resistance and in case of counterattack is authorized. Mussolini."
"Rome, 28 December '35. A.S.E. Badoglio. Given the enemy system I have authorized V.E. the use even on a vast scale of any gas and flamethrowers. Mussolini."
Mussolini and his generals sought to cloak the operations of chemical warfare in the utmost secrecy, but the use of gas was revealed to the world through the denunciations of the International Red Cross and of many foreign observers. The Italian reaction to these revelations consisted in the "erroneous" bombardment (at least 19 times) of Red Cross tents posted in the areas of military encampment of the Ethiopian resistance. The orders imparted by Mussolini, with respect to the Ethiopian population, were very clear:[7]
"Rome, 5 June 1936. A.S.E. Graziani. All rebels taken prisoner must be killed. Mussolini."
"Rome, 8 July 1936. A.S.E. Graziani. I have authorized once again V.E. to begin and systematically conduct a politics of terror and extermination of the rebels and the complicit population. Without the lex talionis one cannot cure the infection in time. Await confirmation. Mussolini."
The predominant part of the work of repression was carried out by Italians who, besides the bombs laced with mustard gas, instituted forced labor camps, installed public gallows, killed hostages, and mutilated the corpses of their enemies. Graziani ordered the elimination of captured guerrillas by way of throwing them out of airplanes in mid-flight. Many Italian troops had themselves photographed next to cadavers hanging from the gallows or hanging around chests full of detached heads. One episode in the Italian occupation of Ethiopia was the slaughter of Addis Ababa of February, 1937 which followed upon an attempt to assassinate Graziani. In the course of an official ceremony a bomb exploded next to the general. The response was immediate and cruel, as he said "Avenge me! Kill them all!". The Black Shirts of the Fascist Militia fired randomly into the Ethiopians present at the ceremony killing large numbers, and immediately after poured out into the streets of Addis Ababa where they killed the Ethiopian civilians that they encountered. They also set fire to homes in order to prevent the inhabitants from leaving and organized the mass executions of groups of 50-100 people. [8]
On March 29, Graziani's forces firebombed the city of Harar. Two days later, the Italians won the last major battle of the war, the Battle of Maychew. Haile Selassie fled into exile on May 2, and Badoglio's forces took the capital, Addis Ababa, on May 5.
Italy annexed the country on May 7, and the Italian king, Victor Emmanuel III, was proclaimed emperor on May 9. Italy merged Eritrea, Ethiopia and Somaliland into a single state known as Italian East Africa.