By contrast to the bulk of the Egyptian Army, who were recruited through annual conscription, the Sudanese units enlisted only long-serving volunteers.

In 1896-98 Kitchener led the advance on Khartoum in command of an Anglo-Egyptian Expeditionary Force composed of British, Egyptian and Sudanese troops.

The Head of the Egyptian Army was the Governor-General and there was still a large garrison, as the territory was huge and the remoter parts, such as Darfur, were not pacified until 1916.

These corps were supported by artillery, engineer, armoured car and machine-gun units; plus medical, signals and transport services.

The main duties of the SDF were internal security: assisting the police in the event of unrest, including restraining inter-tribal violence, cattle raiding and slave trading; or natural disaster.

In December 1933, the Italians probed various positions in the Jebel Uweinat area along the poorly defined border between the Kingdom of Egypt, the Sudan, and ASI.

From 10 June 1940, when Fascist Italy declared war on Britain and France, the SDF was involved in the East African Campaign.

The Italians occupied the railway junction at Kassala, the small fort at Gallabat, and the villages of Ghezzan, Kurmuk, and Dumbode on the Blue Nile.

[12] The Sudan Defence Force fought during the East African Campaign on the "Northern Front" under the command of Lieutenant-General William Platt.

During this invasion, the SDF contributed machine gun companies, howitzer batteries, and other forces (including some homemade armoured cars).

The SDF also played an active role during the Western Desert Campaign along the Sudanese border with ASI in North Africa.

The SDF was used to supply the Free French and then the Long Range Desert Group (LRDG) garrisons of the former Italian Fort Taj at the Kufra oasis in southeastern Libya.

British Military Intelligence in Cairo worked very closely with the SDF and used them in numerous operations during the North African campaign in the Second World War.

In 1942 on instructions from London, British Military Intelligence, Cairo and elements of the Sudan Defence Force were involved with countering Operation Salaam, the infiltration of German Brandenburger commandos into Egypt.

[17] Even after the Tunisian Campaign had ended in Allied victory, SDF patrols were busy thwarting German efforts to land agents behind the lines.

On 15 May 1943, a four-engine aircraft with German markings attempted to land at El Mukaram only to be engaged and shot up by a SDF patrol.

"[20] In March 1954 British troops in the Sudan consisted of one battalion stationed in Khartoum, reporting ultimately to the Governor-General.

[24] One source wrote that Sudan was "the one African Country south of the Sahara to emerge from the colonial period with a military establishment possessing the attributes of an independent national army.

"[25] However internal religious and racial divisions led to the mutiny and disbandment of the Equatoria Corps (recruited from southern black Africans) in 1955 and the commencement of a 17-year civil war.