Black Week

In a disastrous week, dubbed Black Week, from 10–17 December 1899, the British Army suffered three devastating defeats by the Boer Republics at the battles of Stormberg, Magersfontein and Colenso, with a total of 2,776 men killed, wounded and captured. The events were an eye opener for the government and troops, who had thought that the war could be won very easily.

British units were armed with then-modern magazine-fed small arms, the .303 caliber Lee Enfield and Lee Metford, and breech-loading field artillery. Boers were armed with the 7mm 1893 Mauser rifle, and fielded German-built breech-loading field artillery. The British, however, were accustomed to fighting tribal wars with tactics more suited to the Napoleonic era, and had no tactical doctrine in place to fight against a foe also armed with the same modern weapons, and suffered accordingly.

With new, modernized troops came new tactics; only a few months after Black Week, one of the main cavalry divisions led a flanking march that ended with a victory. Besides equipping the cavalry with rapid-firing rifles instead of lances, the new British military doctrine also started using artillery as a defensive unit of the army, and saw innovation in the use of machine guns.

These new volunteers served as a "new face, untainted by defeat and accusations of defeatism…to breathe life back into the campaigns and restore hope at home." Other changes enacted by the British immediately following the Black Week disaster were the mobilization of two more divisions, the calling up of the army reserves, raising a force of mounted cavalry for better mobility, and most importantly by sending volunteers from home overseas which added more than one hundred thousand additional troops by the end of the war.

During Black week, the War Office took primacy, as the Colonial secretary took a back seat in the cabinet, the Boer War raged on. Chamberlain was eclipsed in Cabinet during December 1899. It must have been a blessing in disguise for the man himself: had he accepted Salisbury's initial offer he would have been at the War Office dealing with the difficulties in the Cape. The Liberal Unionist was not going to be a scapegoat for Conservative policy. The reverses and humiliations for the Army hit the London government hard.

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