The 'Siege of Saïo' was fought between primarily Belgian and Italian forces during the 'East African Campaign' (25 March/6 July 1941).

In this protracted episode, Belgo-Congolese troops, British commonwealth forces and local resistance fighters besieged the Italian-held fort in the market town of Saïo in south-western Ethiopia. The siege lasted for several months, culminating in an Allied attack on the Italian garrison which then surrendered.

In the first months of 1941, British and Belgian colonial forces attacked the far western part of Africa Orientale Italiana (Italian East Africa) from the Anglo-Egyptian Sudan and by the end of March had seized the town of Gambela and begun to contain retreating Italian forces, which were massing on a plateau in the mountain town of Saïo (now Dembidolo) under the command of Generale di Corpo d’Armata Carlo de Simone and later Generale d’Armata Pietro Gazzera. The British forces withdrew during the following month and the Belgians advanced along the road to Saïo, where the Italians repelled their advance and compelled them to hold their positions along a nearby stream. Almost no fighting took place in May as heavy rain bogged down the Belgians and turned their supply line from Sudan into mud. Early in June, reinforcements arrived via river and the Belgians laid siege to the Italian supply depot at Mogi. Aggressive patrols, combined with the actions of the Ethiopian resistance and raids by warplanes of the South African Air Force put increased pressure upon the Italian garrison.

At the end of the month Generaal[majoor Auguste Éduard Gilliaert took command of the Belgian forces with orders from the British to attack when an opportunity presented itself. On 3 July, Gilliaert’s men assaulted the base of Saïo mountain and in the afternoon Gazzera sued for peace. On 6 July, the Belgians formally accepted the Gazzera’s surrender together with that of eight other generals and more than 6,000 Italian soldiers.

On 9 May 1936 Benito Mussolini, the Italian dictator, proclaimed the colony of Africa Orientale Italiana created from Ethiopia (after the Italian victory in the 2^nd Italo-Ethiopian War, fought between 3 October 1935 and May 1936) and the existing Italian possessions of Italian Eritrea and Italian Somaliland. On 10 June 1940, Mussolini declared war on France and the UK, which made Italian military forces in Libya a threat to Egypt and those in Africa Orientale Italiana a danger to the British and French colonies in East Africa. Italian belligerence also closed the Mediterranean Sea to Allied merchant shipping and endangered British maritime supply routes along the coast of East Africa, the Gulf of Aden, the Red Sea and the Suez Canal. Egypt, the Suez Canal, French Somaliland and British Somaliland were also vulnerable to attack from Africa Orientale Italiana, but the rearmament plans of the Comando Supremo were not due to mature until 1942 and in 1940, therefore, the Italian armed forces were not ready for military operations against a comparable power.

Prince Amedeo, Duca d’Aosta, was appointed viceroy and governor-general of Africa Orientale Italiana in November 1937, with his headquarters in Addis Ababa, the Ethiopian capital. On 1 June 1940, as the commander-in-chief of the Comando Forze Armate dell’Africa Orientale Italiana (Italian East African armed forces command) and Generale d’Armata Aerea (air force general), Aosta had under his command about 290,476 locally recruited and Italian-born army, naval and air force personnel, and by 1 August mobilisation in Africa Orientale Italiana had increased that number to 371,053. On 10 June, the Regio Esercito was organised in four commands, with the military forces in Ethiopia led by Gazzera.

Aosta had the 40a Divisione fanteria 'Cacciatori d’Africa' and the 65a Divisione fanteria 'Granatieri di Savoia' from Italy, one battalion of Alpini elite mountain troops, one Bersaglieri battalion of motorised infantry, several Milizia Volontaria per la Sicurezza Nazionale or 'Blackshirt' battalions and an assortment of smaller units. About seven-tenths of the men under Italian command were locally recruited Askari. The regular Eritrean battalions and the Regio Corpo Truppe Coloniali (Royal Corps of Somali colonial troops) were among the best Italian units in Africa Orientale Italiana, and included the Eritrean Penne di Falco (falcon feathers) cavalry.

In August 1939, General Sir Archibald Wavell, the British commander-in-chief in Egypt and the Middle East, ordered the creation of a plan for the covert encouragement of a rebellion in the western Ethiopian province of Gojjam, which the Italians had never been able entirely to repress after the end of the 2^nd Italo-Ethiopian War. In September, Colonel Daniel Sandford arrived to run the project but until the Italian declaration of war, the conspiracy was held back by the British policy of appeasement, intended to avoid a simultaneous war with Germany and Italy. Mission 101 was formed to co-ordinate the activities of the Arbegnoch (Amharic for Patriots). In June 1940, the deposed Emperor Haile Selassie arrived in Egypt and in July travelled to Sudan to meet Major General W. Platt, commander of the Sudan Defence Force, and discuss plans for the recapture of Ethiopia, a scheme about which Platt had reservations. In July, the British recognised Selassie as emperor of Ethiopiam and in August Mission 101 entered Gojjam province to reconnoitre. Sandford requested that supply routes to the area to the north of Lake Tana be established before the rains ended and that Haile Selassie should return in October as a catalyst for the uprising. Gaining control of Gojjam required the Italian garrisons to be isolated along the main road from Bahrdar Giorgis, in the area to the south of Lake Tana, to Dangila, Debra Markos and Addis Ababa, and this prevent the Italian forces from concentrating against the Arbegnoch. Italian reinforcements arrived in October and patrolled more frequently, just as dissension between local potentates were being reconciled by Sandford’s diplomacy.

The Frontier Battalion of the Sudan Defence Force, created in May 1940, was joined in Khartoum, Sudan’s largest city, by the 2^nd Ethiopian and 4^th Eritrean Battalions, raised from émigré volunteers in Kenya. Operational centres, each comprising one officer, five non-commissioned officers and several picked Ethiopians were formed and trained in guerrilla warfare, to provide leadership cadres, and £1 million was set aside to finance their operations. Major O. C. Wingate was sent to Khartoum with an assistant to join the headquarters of the Sudan Defence Force. On 20 November, Wingate was flown to Sakhala to meet Sandford. The Royal Air Force bombed Dangila, dropped propaganda leaflets and supplied Mission 101, which raised Ethiopian morale, which had been severely shaken by Italian air power since the 2^nd Italo-Ethiopian War. Mission 101 persuaded the Arbegnoch in the area to the north of Lake Tana to spring several ambushes on the road linking Metemma and Gondar, and the Italian garrison at Wolkait was withdrawn in February 1941.

At the end of the 'Battle of Belgium' in May 1940, the only proper force left under Belgian command was the Force Publique (Public Force, the colonial army) of the Belgian Congo in west central Africa, which thus comprised the bulk of the Free Belgian forces. Consisting of Belgian officers and 15,000 native other ranks, it was well equipped, well disciplined and dispersed throughout the colony. Through the year, the Force Publique’s defence obligations were considered too important for it to be spared for offensive operations. The Allies were uncertain of German intentions toward Portuguese Angola, the Congo’s southern neighbour, and the extent of Vichy French influence in French Equatorial Africa to the north. Belgian members of the Force Publique grew impatient with the colonial administration’s perceived inaction and the garrison of Stanleyville mutinied in protest. The governor general, Pierre Ryckmans, was forced to send a senior member of his staff to calm the situation and explain the importance of the Congo’s economic contribution to the war.

Meanwhile, Ryckmans and Luitenant-generaal Paul Ermens, the vice-governor of the Congo and commander of the Force Publique, discussed with the South African and British military missions in Léopoldville the possibility of sending an expedition to Africa Orientale Italiana. The two major problems with such an undertaking were the fact that Italian territory was thousands of kilometres away and Belgium was not at war with Italy. The Belgian government-in-exile was wary of declaring war on a country whose royal family had dynastic links with its own, though this attitude changed after it became known that Italian aircraft based in occupied Belgium were attacking the UK in the 'Battle of Britain' and after an Italian submarine had sunk a Belgian cargo ship. A declaration of war was eventually delivered on 23 November 1940, and two days later Ryckmans proclaimed that a state of war existed between the Congo and Italy.

Free French forces consolidated their control over Equatorial Africa in the 'Battle of Gabon' and greater German involvement in the 'Balkan Campaign', begun by Italy in 1939, made the possibility of intervention in Portugal remote. The staff of the Force Publique and the Belgian government then resolved to assemble an expedition to fight in Africa Orientale Italiana. Plans were co-ordinated with the British and in February 1941, after an extended period of preparation, the first group of 8,000 troops and porters set out from the Congo for Ethiopia. Starting in Stanley Pool, they were carried in a dozen 10-ton barges and a tug up the Congo river to Aketi. The expeditionary force then took the Vicicongo line (a narrow-gauge railway) from Aketi to Mungbere and was then transported by truck to Juba in south-western Sudan, where they took to the White Nile river. After five days of travel, the first Belgo-Congolese battalion reached Malakal and marched to the border town of Kurmuk before entering Ethiopia.

Following Italy’s declaration of war on France and the UK on 10 June 1940, the 'East African Campaign' began as military forces of the British empire engaged the Italian Comando Forze Armate dell’Africa Orientale in Italian East Africa. After a series of actions in 1940, British colonial forces from Anglo-Egyptian Sudan invaded the territory and eventually a salient formed around the Baro river. In March 1941, the Italian forces began to withdraw from the salient under increasing pressure. On 8 March the first battalion of the Belgo-Congolese expeditionary force marched from Kurmuk toward the Italian-held town of Asosa. The expeditionary force attacked three days later in conjunction with troops of the King’s African Rifles, forcing the Italian garrison to retreat to Gidami. Next, the Belgians and Congolese began attacking the town of Gambela directly from the west while two companies of the 2/6^th K ings’s Afroican Rifles under Captain J. W. E. Mackenzie were sent to outflank it and sever its link with the Italian headquarters at Saïo under the command of de Simone. The Belgians were concerned that the Italians might attempt an offensive over the weakly defended Sudanese border, but by taking Gambela they could force Gazzera’s forces in western Ethiopia into a defensive position. On 22 March, the King’s African Rifles' companies attacked, but withdrew to the south when a planned Belgian assault failed to materialise. The Italians were nevertheless surprised by the flanking manoeuvre and retreated to Saïo.

On 25 March, the Belgo-Congolese battalion and the two companies of the 2/6^th King’s African Rifles occupied Gambela. Exhausted by their journey from the Congo and suffering from dysentery and a lack of artillery, the 1,000 Belgians and Congolese could undertake no further offensive action. Instead they made moves to contain the Italian forces around Saïo from the west, while British troops under Lieutenant General A. G. Cunningham conducted operations in Somalia and eastern Ethiopia. The Arbegnoch also threatened the Italian positions. During April, the Italian forces burned the elephant grass along the Saïo plateau to provide themselves with unobstructed fields of observation and fire, and in that same month the men of the 2/6^th King’s African Rifles were withdrawn to the Dabus river to link with the rest of their unit in the containment of the Italian garrison in Mendi.

The Italians mined the 40-mile (64-km) length of the road linking Saïo and Gambela that led to the Saïo plateau 4,000 ft (1220 m) above the surrounding area. The Belgians began slowly advancing but encountered Italians at the Bortai stream, which ran perpendicular to the road. The Belgians were strengthened by the arrival of a Stokes mortar company and another battalion. Now totalling 1,600 soldiers and 600 non-combatant porters, they nonetheless lacked the strength to seize the plateau. With the Italians receiving reinforcements of troops retreating from the east, the Belgians decided to keep the initiative to disguise their small numbers.

Three days of cold weather and rain preceded the offensive. On 15 April, Luitenant-kolonel Edmond van der Meersch led an attack on the stream. A Belgian lieutenant scouting in no man’s land was ambushed and killed. A Belgian sergeant caught three Italian officers at gunpoint but lowered his revolver when they claimed to be English, thinking the King’s African Rifles might have despatched a liaison party to the area. He was then shot by snipers concealed in the bush. there followed a fight in which four Congolese soldiers were killed. Three Italians and an estimated 40 Eritrean Ascari were killed, and about 70 Ascari were wounded.

During the ensuring stalemate, the Belgians studied the Italian tactics, which included the siting of pairs of snipers and artillery spotters in trees guarded at the bases by infantry squads. Their artillery barrages were usually avoided by Belgian patrols, though they would continue up to an hour after they withdrew. On 21 April, the Italians launched a large counterattack. After a two-hour bombardment, Eritrean troops armed with automatic weapons and hand grenades and covered by Galla snipers penetrated the Belgians' left and right flanks. With van der Meerch’s battalion suffering the brunt of the assault, the Belgians retreated behind a pair of hills that obscured them from Italian observers, which the latter then seized.

By May, the Belgian strength had increased to 2,500 men, under the command of Luitenant-kolonel Leopold Dronkers-Martens. The rainy season had also begun by this time, turning the main road from Sudan into mud, cutting off communications and the movement of supplies. The Baro and Sobat rivers were still too low to permit the passage of supply barges from the White Nile river, and the nearby Gambela airfield was too small for transport aircraft. The only means of supply was by airdrop, and this compelled the Belgians and Congolese to halve their rations. Several porters attempted to bring food on foot 40 miles (64 km) from Sudan, but died of fatigue and undernourishment. Some of the officers resorted to stripping the camouflage netting from their trucks to use for fishing in the Baro river, and there were frequent outbreaks of the thiamine-deficiency disease beriberi. Camped on fertile soil and well supplied, the Italians faced no such problems, and were able to make frequent air attacks on the Belgians.

The situation of the Belgian-led force remained difficult until a time early in June, when the Baro and Sobat rivers rose enough for reinforcements from the Congo to reach them. They then decided to try to sever the Italian supply line between Saïo and Mogi, another town on the plateau. To hold the line near the Bortai stream, the Belgians could spare only around 250 men for an attack. It was hoped that cutting off the Italians would allow the British, stalled in their advance at Gidami, to move to the south and encircle Saïo. On 9 June the Belgian force attacked Mogi, their flank covered by the arrival of a new battalion from the Congo, but the 300-man Italian garrison held off the assault. Believing that the town could only be taken at a heavy cost, the Belgians instead fortified their positions around Mogi and sent patrols to mount ambushes on the road by which Saïo was being supplied.

At the regular front, Dronkers-Martens ordered his troops to increase their patrol activities on the Saïo plateau in an effort to make the Italians believe that they were facing superior forces. The Belgians used shoot-and-scoot tactics, avoiding counterbattery fire and leaving the Italians with the impression that they were facing several consistent points of fire. Gazzera tripled the size of the Mogi garrison and the Italians began to reduce their activity as the Belgians became bolder. Eventually the South African Air Force committed three Hawker Hart single-engined biplanes to undertake the regular bombing of the Saïo fortress and strafe the surrounding roads. In the east, British forces pressed onward, forcing Gazzera to abandon his own headquarters in Jimma in the middle of June and withdraw to Saïo. The 2/6^th King’s African Rifles secured Gidami and headed to the south-east to cut the road linking Saïo and Yubdo. By the end of the month, the British had driven the Italians from the western bank of the Didessa river. The 23a Divisione coloniale and 26^th Divisione coloniale were ordered to retreat through Yubdo, to make their final stand at Saïo. Heavy rain, actions of the Arbegnoch and the South African Air Force’s raids compounded the Italian problems.

Gilliaert arrived from the Congo before the end of the month. On 27 June Platt, advancing with British forces from Sudan, ordered the Belgians to attack the Italian positions if an opportunity presented itself and Gilliaert immediately undertook preparations for an offensive. The plans for taking Mogi were abandoned and the Belgians were to concentrate their efforts against Saïo, so all but 50 of the men besieging Mogi were redeployed.

Believing the British pursuit to be closer than it actually was, Gazzera ordered the bridge over the Indina river, some 40 mi (65 km) to the east of Saïo, to be blown but thereby trapped his own forces. Though still outnumbered, the Belgians decided to carry on with their offensive. On 2 July, they forced their way over the Bortai stream, and at dawn on the following day, the Belgian advance posts opened fire on Saïo and 30 minutes later the Belgian artillery went into action. The Italians responded with heavy counterbattery fire. One Belgian battalion advanced on Italian machine gun positions on the two hills that had been occupied since April. The reserve battalion covered their left flank and Gilliaert dispatched the third battalion under van der Meersch to the right flank down a goat path that had been mapped by patrols over a fortnight. Two artillery batteries gave them covering fire. The Belgians captured the hills and the Italians, flanked on their left by van der Meersch’s troops, were unable to make it back to their fortifications at the top of Saïo mountain. With the road linking Saïo and Gambela under artillery fire, the Italians fell back onto the plain to their right. Meanwhile, the 2/6^th King’s African Rifles launched an attack on the road linking Saïo and Yubdo, continuing this success throughout the next day.

The Italians were under the impression that they were facing three Belgian divisions with South African reinforcements, and also had left provisions for only two months. Gazzera radioed to the Allies in Addis Ababa his intentions to negotiate a surrender with the Belgians. The latter were preparing for another assault when at 13.40 two staff cars bearing white flags drove down the mountain. In them were eight Italian generals, a Catholic priest and Gazzera’s chief-of-staff. Gilliaert met them a short distance away from the Bortai stream near Gambela, where the Italians asked that all hostilities in the area to the south of the Blue Nile river cease and that their army be granted the honours of war. Gilliaert accepted and on 6 July drove into Saïo to receive the formal surrender of the Italian forces.

With Gazzera’s surrender, Gondar became the last area in Ethiopia under Italian control. Saïo market was reopened three days after the end of hostilities and Belgian engineers repaired the road linking Saïo and Gambela. At Gazzera’s request, Gilliaert guaranteed the Eritrean Askari safe passage to British prisoner of war camps in the east and sent Congolese guards to protect them from Ethiopian retaliation. The Belgian force soon returned to the Congo after securing the first major victory for the Free Belgian forces, and their morale was greatly improved by this success.

The Belgo-Congolese force lost 462 men during the conflict, four-fifths of them to disease, and it was estimated that the Italians lost about three times as many. Some 6,454 Italians were taken prisoner, this total including including Gazzera, eight other generals and 3,500 Askari, along with 20 pieces of artillery, 200 machine guns, 250 trucks and 500 mules. Though numbering only about 3,000 soldiers and 2,000 porters, the Belgo-Congolese force had to manage 15,000 prisoners in the former Galla-Sidamo Governorate after the campaign.