The Gordon Relief Expedition (1884–85), was a British mission to relieve Major-General Charles George Gordon at Khartoum, Sudan. Gordon had been sent to the Sudan to help Egyptians evacuate from Sudan after Britain decided to abandon the country in the face of a rebellion led by self-proclaimed Mahdi, Mahommed Ahmed.

Not wanting to be involved in the costly suppression of the rebellion led by Mahommed Ahmed, the United Kingdom ordered Egypt to abandon its administration of the Sudan in December 1883. The British government asked General Gordon, former Governor-General of Sudan, to go to Khartoum and aid in the evacuation of Egyptian soldiers, civilian employees and their families. Travelling from London, General Gordon reached Khartoum on 18 February 1884. He immediately began sending women, children and wounded soldiers back to Egypt as the military situation deteriorated in the Sudan and the south of the country was in danger of being cut off from Egypt by the Islamic Mahdist army. Britain withdrew its troops from the Sudan until Khartoum was the last outpost remaining under British control.

Gordon differed with the British government's decision to abandon the Sudan. He thought that the Islamic revolt had to be crushed for fear that it might eventually overwhelm Egypt. He based this on the Mahdi’s claim of dominion over all Islamic lands. Defying orders from the British government to withdraw, General Gordon, leading a garrison of 6,000 men, began the defence of Khartoum. On March 18, 1884, the Mahdist army laid siege to the city. The rebels stopped river traffic and cut the telegraph line to Cairo. Khartoum was cut off from resupply, which led to food shortages, but could still communicate with the outside world by using messengers. Under pressure from the public, in August 1884, the British government decided to reverse its policy and send a relief force to Khartoum.

In mid-November, the expedition received word from General Gordon that he could only survive the siege for another forty days. The expedition was attacked by rebels at Abu Klea and Abu Cru, but was able to repel the rebels both times. Progress up the river was slow and often the boats had to be pulled through rapids by rope from shore. Realising that time was running out for General Gordon in Khartoum, Wolseley split his force into two columns. He sent 2,400 men by camel on a 280 km shortcut across the desert to avoid the Great Bend of the Nile and reach the city sooner. The remaining 3,000 soldiers continued up the river.

On 26 January 1885, Khartoum fell to the Mahdist army of 50,000 men. At that time of year the Nile was shallow enough to cross by wading and the Mahdists were able to breach the city’s defences by attacking the poorly-defended approaches from the river. The entire garrison was slaughtered, including General Gordon. His head was cut off and delivered to the Mahdi. Two days later the relief expedition entered the city to find that they were too late.

The Anglo-Egyptian conquest of Sudan in 1896–1899 was a reconquest of territory lost by the Khedives of Egypt in 1884 and 1885 during the Mahdist War. The British had failed to organise an orderly withdrawal of Egyptian forces from Sudan, and the defeat at Khartoum left only Suakin and Equatoria under Egyptian control after 1885. The conquest of 1896-99 defeated and destroyed the Mahdist state and re-established Anglo-Egyptian rule, which remained until Sudan became independent in 1956.

The defeat of the Khalifah's forces at Omdurman marked the effective end of the Mahdist state, though not the end of campaigning. Over 11,000 Mahdist fighters died at Omdurman, and another 16,000 were seriously wounded. On the British, Egyptian and Sudanese side there were fewer than fifty dead and several hundred wounded. The Khalifa retreated into the city of Omdurman but could not rally his followers to defend it. Instead they scattered across the plains to the west and escaped. Kitchener entered the city, which formally surrendered without further fighting, and the Khalifa escaped before he could be captured.

Source - Wikipedia