The Battle of Kassala ( from the border with Eritrea) was fought in Sudan, near Kassala, in the Second World War, on 4 July 1940. The battle was early in the East African campaign. The battle led to an Italian occupation that lasted six months. On 18 January 1941, forces led by General William Platt occupied the nearby town of Gallabat and the Italian command ordered the evacuation of Kassala on 21 January.
Before the Italian declaration of war, Mussolini intended a defensive strategy in (AOI) with tactical offensives to protect Eritrea by attacking French Somaliland (, now Djibouti) and conducting limited attacks on Sudan. The Italian army in the AOI had one metropolitan division, the equivalent of two more European divisions, that was short of heavy weapons and transport and seven understrength colonial divisions. A force was concentrated near the Sudan border for an attack on Kassala, comprising two colonial brigades, four squadrons of cavalry, approximately 24 light tanks, medium tanks and armoured cars and ten batteries of artillery.
From the day of entry into the war, the Italian troops limited themselves to maintaining a defensive position, except for a few attacks across the border and some raids. Some of these operations led to the occupation of Moyale and the Mandera salient in Kenya. On the border with Sudan, on 3 July 1940 it was the British who took the initiative by attacking the Eritrean town of Metemma but were repelled.
The attack, planned and led by the governor of Eritrea and Amhara, General Luigi Frusci, assisted by General Vincenzo Tessitori, who also led one of the columns, was carried out with a notable deployment of forces, especially Askari divided into three columns, called Gulsa East, Gulsa West and Central, with air support. The Gulsa West column moved in lorried. To these were added some cavalry squadrons which constituted the vanguard. At on 4 July 1940, the three Italian columns advanced towards Kassala from three directions, with starting points apart. The first attack bypassed the Casala and Mocram mountains, was by the cavalry led by Lieutenant Francesco Santasilia of Torpino who was killed.
Kassala had a garrison than 500 men of the SDF and local police, who remained under cover during a twelve-hour bombardment by the and then emerged to engage the Italians. The defenders knocked out six Italian tanks and inflicted considerable casualties on the attackers. The SDF resisted tenaciously and even sent twenty tanks into the fighting, which were attacked by the . At the Italian cavalry squadrons entered Kassala and the Sudanese units commanded by British officers fled.
In the city of Kassala, the 12th Brigade of the colonial army built anti-tank obstacles and set up machine-gun nests to cover them. The Italians were expecting to find anti-British feeling amongst the local population and were disappointed to find that many of the locals were lukewarm. During the Italian offensive in Kassala, a battalion of Italian colonial forces and a group of irregular soldiers known as bande attacked the Commonwealth position at Gallabat and managed to drive the No 3 Company of the Eastern Arab Corps back. The town of Karora was taken without resistance when the Sudanese police were ordered to withdraw and the town of Kurmuk was taken on July 7 when another battalion and two bande of irregular soldiers, supported by artillery and aerial bombardment, defeated a company of about 60 Sudanese policemen after a very brief engagement.
Among the loot recovered at Kassala was found the diary of a British officer in which the following was specified: "The order is to resist to the bitter end at Kassala against the Italians". At the same time, General Pietro Gazzera occupied the forts of Gallabat and Kurmuk, in Anglo-Egyptian Sudan. An Italian map captured on 25 July showed around 20,000 British and Sudanese troops in Kassala province. A British attempt to recover Gallabat in November 1940 was defeated by the defences set up by the Italians under Colonel Castagnola.
The capture of Kassala incurred many casualties compared to the strategic value of the location. The offensive did not continue into the hinterland, allowing the British to reorganise and counter-attack. A special motorised unit called Gazelle Force was created to counter the Italians, under the command of Colonel Frank Messervy. On 18 January 1941, Platt occupied the Eritrean city of Gallabat and on 21 January 1941, the Italian command, under British pressure, decided to evacuate Kassala and other vulnerable positions to shorten the front, a manoeuvre carried out as communicated by bulletin no. 228 of the Italian Supreme Command of 22 January 1941.
The Italian forces, led by General Orlando Lorenzini, retreated in an orderly fashion to Agordat, where the Italian troops awaited the British forces on the defensive during the Battle of Agordat, that anticipated the decisive Battle of Cheren. The Italian forces of Gallabat, under the command of General Agostino Martini and General Guglielmo Nasi retreated to Gondar. During the retreat, to delay the British advance, Lieutenant Amedeo Guillet, at the head of the Amhara cavalry, charged the enemy, disorganising their troops. The British officer who was the victim of the assault later wrote,