One result of Black Week (10-17 December 1899) was the appointment of Field Marshal Lord Roberts to command the British forces in South Africa. Roberts arrived in Cape Town on 10 January. His plan was not that much different from Sir Redvers Buller’s original plan when he had arrived – to strike into the Orange Free State from the north east Cape Colony, capture the capital at Bloemfontein, and then move north east along the railway to Pretoria. Buller had allowed himself to be distracted by the problems further east, in Natal, while the siege of Kimberley had dominated proceedings in the west, largely due to the presence of Cecil Rhodes in the besieged town.
Roberts decided to ignore the main Boer position at Magersfontein, where Lord Methuen had come to grief on 11 December 1899 during Black Week. Instead, he would launch his army east, and head directly for Bloemfontein. The cavalry, under General Sir John French, would accompany the infantry for a short distance, then cross the Modder River and ride to the relief of Kimberley. Roberts expected the Boers at Magersfontein and around Kimberley to withdraw east once it became clear that Bloemfontein was threatened.
In order to achieve this plan, Roberts drew in troops from all across Cape Colony. His most urgent need was for more cavalry. He only had one brigade of cavalry, and eight batteries of horse artillery. His solution was to create two brigades of mounted infantry, which gave French the numbers he would need if he ran into any serious opposition.
The eastern route to Kimberley was blocked by two rivers – the Riet and the Modder. In order to cross the Riet, Roberts had to start with a march twenty miles south east along the Riet. French’s cavalry division crossed the Riet at De Kiel’s drift on 12 February. The next day they made a twenty five mile long trek across the dry veld between the Riet and Modder rivers. His true target was Klip drift, a ford across the Modder. At first he made for Klip Kraal drift, eight miles further east, in order to deceive the watching Boers. Late in the day he changed direction, and was able to cross the Modder without serious opposition. On the evening of 13 February French and his cavalry were safely across the Modder river. They spend the next day resting, and waiting for VI infantry division to arrive to guard the river crossings. After a forced march, that division arrived late on 14 February.
The Boer commander at Magersfontein, Piet Cronje, could not believe that a British commander had willingly abandoned the railway. For some days he believed that Roberts was either retreating south east, or that the move was a feint designed to pull him out of the Magersfontein position, which was now heavily fortified. He can hardly be blamed for this – neither Methuen or Bullers would have taken the risk. However Cronjé did make one move which could have caused disaster, moving two commandos east to watch French. This force took up position on some kopjes north west of Klip Drift. The Boer forces that had been shadowing French south of the Modder had also crossed over, and now occupied the hills north of the drift. French was faced by a potentially dangerous position. The Boer line formed a semi-circle around the edge of a shallow valley, apparently blocking his route onwards.
French now made a bold but risky decision. The line of hills was broken by a pass at the head of the valley. French decided to send his entire command on a charge up the valley and through the nek. If the nek was weakly held, then the cavalry division would simply smash through the line and be free to complete their journey to Kimberley. If the nek was strongly held, then French’s charge might have ended in utter disaster.
French was lucky. After a five mile gallop along the valley, the Cavalry Division swept through the pass and broke through the Boer lines. Out of a force 5,000 strong, French lost only one man dead and twenty wounded. The road to Kimberley was now open.
Kimberley was in sight by 2.30 pm. Communications with the garrison were opened by heliograph. French had successfully kept his operation secret, and so at first the defenders of Kimberley refused to believe that French was who he claimed to be. Eventually they were convinced, and by 6.30 pm that evening French and his men were in Kimberley. With British reinforcements in Kimberley, the Boer forces outside the town abandoned their lines and retreated.
The relief of Kimberley was one of the more impressive British operations of the war. It opened a period of great success for Roberts that would soon lead to the capture of Bloemfontein. However it came at a heavy cost in horses. French spent much of 16 February trying to find the retreating Boers. At the end of the day, when he was called east to Paardeberg, only 1,200 horses were fit for duty. The relief of Kimberley had been a political necessity more than a military one, and Roberts would pay for it in missed chances later in the campaign.