The emergence of insecurity in the Italian colonies of East Africa – especially starting from the end of 1914 – and the confirmed impossibility of maintaining peaceful economic and commercial relations with Abyssinia, imposed on Italy the need to provide some precautionary measures that they first materialized (January 1935) in the sending of two national divisions, respectively to Eritrea and Somalia. As the state of tension between Italy and Abyssinia continued and gradually increased, supported and ill-advised by European powers, the possibilities for peaceful settlement decreased over the course of the year, given the intransigence of the Addis Ababa government and the spirit of absolute incomprehension demonstrated by the League of Nations regarding the rights and Italian interests in East Africa. It was therefore necessary, after having sent and equipped an adequate expeditionary force, suitably located in Eritrea and Somalia and composed of army divisions and black shirts, as well as large units of indigenous troops, to parry all possibility of abyssinian aggression in force, before it was too late.
On the Somali front, in addition to minor operations that gave Italy possession of Dolo, in the western sector, and of Gherlogubi, about 40 kilometers from Ual Ual, an offensive was launched in the central sector to the NE. of Mustahil, with the aim of occupying the Shaveli region. An attack by dubat and irregular gangs under the command of Olol Dinle, Sultan of the Sciaveli, who had previously submitted to General Graziani, commander of the Italian forces in Somalia, was launched against Dagnerei key of the Abyssinian positions on October 18, after aerial bombardment.. Dagnerei occupied, after a fierce struggle, the possession extended to the north as far as Callafò.
After the victorious action against Dagnerei, the Italian forces occupied the coastal villages of Uebi Scebeli and victoriously supported some clashes in the Giuba sector. At the beginning of November, the Italian command, having heard that the Ethiopians were making strong concentrations of troops and materials in the area of Gorrahei, on the Fafan, decided to invest the position, firmly fortified with modern preparations. Two columns, driven respectively by Gherlogubi and Belet Uen, carried out a converging advance on Gorrahei, while the air force carried out very effective bombings after which the enemy abandoned the position. On the night of November 6, 1935, Italian speedy elements entered Gorrahei, passed it and pursued the fleeing enemy. On day 11 a autocolonna made contact with the enemy in the upper Fafan valley, reinforced by a thousand regular trucks from Dagabur. The clash – the first that took place against the modernized Ethiopian forces – ended with full victory, which led to the conquest of Gorrahei, the advanced stronghold of the Giggiga-Dagabur defensive line and the main military center of a vast sector of the Ogadēn.
The Abyssinian forces on the Somali front were evaluated as follows: a body of 50,000 men under the command of the degiac Nosibu concentrated in the Giggiga-Sassabaneh area; a central mass, of somewhat lesser strength, slowly advancing along the Uebi Scebeli under the command of the degiac Bejenè Merid; a mass of 30,000 men, under the command of Ras Destà, concentrated at about 80 km. north of Dolo.
Of all the enemy movements, that of ras Desta appeared to be the most dangerous. On 22 November, the vanguards of the Ras Destà army had been beaten by the Italians at Lamma Scillindi, which had been occupied, and large concentrations had been discovered and bombed by the air force between Neghelli and Filtu. Ras Destà’s plan, conceived not without breadth of vision, aimed to operate against the Dolo sector, to undermine the Somali front and then take away the ports of Mogadishu and Chisimaio from Italy, or at least aim against the eastern sector, in ‘Ogadēn. Ras Destà then proceeded from its collection centers – the town of the Arussi and the region of the Galla Lakes – along the caravan routes that follow the three rivers flowing into the Giuba near Dolo. In early January 1936,
Aware of this favorable situation, General Graziani worked to detach Ras Destà’s army from the borders of the Kenyan colony, from which it drew supplies. On 12 January, General Graziani advanced a column along the Ganale Doria, a second, truck-mounted, on the Neghelli truck, and a third along the Daua Parma. The enemy put up bitter and relentless resistance along those routes, using caves and a complete defensive system (redoubts, trenches, fences and machine gun nests). The fighting lasted with increasing ardor until the 16th, when the enemy, decidedly overwhelmed, hastily abandoned the positions of Bogol Magno and Galgalo, chased by the truck-mounted column, which was heading towards the plain of Filtù, while the other two columns continued towards their respective objectives. Meanwhile, General Graziani with a fast truck-mounted detachment marched on Neghelli, capital of the Galla Borana, where he entered on January 20. The other columns also continued their advance, and that of the Daua Parma occupied Malca Murri. The enemy had suffered enormous losses.
The activity of the Italian aviation was explained on a large scale on the Somali front. The actions were carried out in the days between March 22 and April 10, with the main tasks of recognizing the possibility of reconstituting the southern Ethiopian front; to secure the core of the Ethiopian forces in the Bale sector, methodically hammering them in vital supply centers; and finally, to begin the preventive work of destroying the bases of the army of the degiac Nasibu that blocked the way to Harar. In order to carry out the first task, reconnaissance actions were carried out accompanied by some bombing action against Ethiopian nuclei sighted. The hammering of the Ethiopian forces in Bale was carried out with particular violence, and special emphasis deserves the raid on the important logistics center of Goba whose warehouses were destroyed. Finally, there were very violent bombings against Giggiga, Harar, Sassabaneh, nerve centers of the opposing resistance. The logistic systems, warehouses, depots, military buildings, and the fortification works were subjected to a very severe test by the Italian aviation devices that carried out mass action.
After the effective aerial preparation, General Graziani on April 15, 1936 arranged the advance in the upper Ogadēn, which was carried out along three routes; the western one, from Danane to Gianagobò, Bircut, Segag, Dagamedò; the power station, from Gebradarre, to Uarandab and Sassabaneh; and the eastern one, from Gherlogubi, Biat-Dida, Curati. Having won the first enemy resistance to Gianagobò in a characteristic battle of encounter, which lasted from 15 to 17 April, the Italian command decisively launched all the columns towards the achievement of the assigned objectives. It appeared from the information gathered that the degiac Nasibu had concentrated his forces in the quadrilateral, firmly organized in defense, of Hamanlei-Bullale-Sassabaneh-Guna Gadu. On the 24th the action entered its decisive phase, proceeding to the investment of the Sassabaneh entrenched camp, while Hamanlei and Guna Gadu were occupied. The raging of bad weather caused the Italian forces considerable difficulties to which the fierce resistance of the enemy was added, but the columns, finally able to overcome the defenses of Sassabaneh, were able to concentrate on April 30 in Dagabur, thus opening the way to Giggiga and Harar, now abandoned by the enemy who was turning on a precipitous course. On the evening of the 5th, truck-mounted elements occupied Giggiga, while other departments focused on Harar, where General Graziani entered on 8 May. Immediately afterwards another column pushed on Dire Daua, taking possession of it on the 9th and joining up with an infantry unit coming from Addis Ababa by means of the Djibouti railway. Thereby, the extreme avant-gardes of the northern and southern armies came into contact, bringing about the joining of the two fronts. Throughout the 1935-1936 campaign in East Africa, v. App.