By taking command in person in Natal, Buller had allowed the overall direction of the war to drift.

Because of concerns about his performance and negative reports from the field, he is replaced as Commander in Chief by Field Marshal Lord Roberts.

Roberts quickly assembles an entirely new team for headquarters staff and he has chosen military men from far and wide: Lord Kitchener (Chief of Staff) from the Sudan; Frederick Russell Burnham (Chief of Scouts), the American scout, from the Klondike; George Henderson from the Staff College; and Neville Bowles Chamberlain from Afghanistan.

Like Buller, Roberts had first intended to attack directly along the Cape Town–Pretoria railway but, again like Buller, had been forced to relieve the beleaguered garrisons. 

Leaving Buller in command in Natal, Roberts masses his main force near the Orange River and along the Western Railway behind Methuen's force at the Modder River, and prepares to make a wide outflanking move to relieve Kimberley.