The political and economic struggle for control over South Africa between the British and the Boers erupted a second time in October 1899. A Boer offensive resulted in the sieges of Ladysmith, Kimberley, and Mafeking, threatening loyal British settlers and economic interests. Against his better judgment, General Buller divided his forces to satisfy immediate political and public interests. The result was the disastrous 'Black Week' of mid-December 1899, when all three British armies were stopped in their tracks at the Battles of Magersfontein, Stormberg, and Colenso. Supplies were readied, volunteers were recruited, and more divisions were mobilized. Over the next year, thanks to an overwhelming numerical advantage, the British regrouped and their advance succeeded in relieving the besieged towns and capturing and the Boer capitals. The Boer commandos in the field, however, refused to surrender and abandoning set-piece battles, they turned to guerrilla tactics. Lord Kitchener’s employment of a blockhouse system, a network of concentration camps, and scorched earth policy eventually broke Boer morale and their ability to continue the struggle. The South African War was Britain’s largest and most costly small war. Nearly half of a million British and Imperial troops fought; 22,000 never came home.

In 1878, Russia challenged British interests in Afghanistan by sending a mission to Kabul, which the Afghan Amir, Sher Ali Khan, appeared to have welcomed. In defence of his forward policy, the British Viceroy in India, Lord Lytton, sent his own emissary. When he was denied entry, the British issued an ultimatum which the Amir rejected. The British invaded in order to secure regime change. Afghan forces included both traditional irregular militias and regulars trained with British weapons by former Indian NCOs. They enjoyed superior numbers, local knowledge, mobility, and some enterprising commanders. British superiority in weapons, discipline, and training was marked. They also adopted khaki uniforms which replaced the traditional scarlet, which frustrated the Afghan use of the long-range jezail. These advantages enabled the defeat of Afghan forces under the new Amir, Ayub Khan, at the Battle of Ahmed Khel (19 April 1880). British and Indian forces were insufficient in numbers, however, to control much of the country. A defeat at Maiwand led to a renewed British commitment and General Sir Frederick Roberts’ successful 300-mile march brought decisive victory at Kandahar. The Amir was replaced with a more compliant leader, and the British withdrew.