Boer War — fought 1899–1902 between the British Empire and the Boer (Dutch settler) republics of South Africa. The British won, but only after extraordinary losses, disasters, setbacks, and the greatest expenditure of men and treasure since the Napoleonic Wars.
Like most wars, it was supposed to be over in months. The difficulty in defeating the Boers – an impromptu army of farmers and draper's assistants – proved a profound shock to the Imperial psyche. In the words of Rudyard Kipling the war was "no end of a lesson".
War File: The Boer War – Story of Britain's Last Great Imperial War.
Outline — properly it's called the Second Boer War (the first having occurred in the 1880s). What is now South Africa was then divided between expanding British settlements on the coast (Cape Colony, Natal) and inland Boer republics (Transvaal, the Orange Free State). The immediate cause of war was the refusal of the Boer leaders to grant political rights in their territories to Uitlanders ("foreigners", mostly British colonists). But the deeper cause was that gold and other minerals had been discovered in the Boer states: the British sought control of the mines.
When Boer commando attacks continued, the British implemented a scorched-earth policy: Boer farms were destroyed and Boer civilians were forcibly "concentrated" in camps. Over 26,000 women and children died in these "concentration camps" (the first usage of the term), provoking international outrage. The Boers finally accepted defeat at the Peace of Vereeniging, 1902. The Union of South Africa was formed of the British and Boer territories, which soon afterwards (1910) became a self-governing dominion in the British Empire.
Boer War and Ireland — the Boer War was the first major British war since the Childers reforms of 1881, when the old British numbered regiments were reorganized into territorial units. (Thus the 102nd and 103rd formed the Royal Dublin Fusiliers.) Irishmen had for centuries fought in the British Army, in numbers disproportionate to population; but in the Boer War, their Irishness was conspicuous by regiment (RDF, Royal Munster Fusiliers, etc.) In recognition of the dedication and bravery shown by her Irish regiments in fighting the Boer, Queen Victoria granted them the privilege of wearing shamrock on St Patrick's Day.
In fact, Irishmen had fought on both sides. An Irish Brigade was raised to fight with the Boers against the Empire, officered by advanced nationalists but recruited mostly from Irish or Irish-American miners already living in the Transvaal. At various points in the war, Irishman fought Irishman:
Irish public opinion divided fairly evenly between pro-Boer and pro-Empire. But the blatant anti-war demonstrations in Dublin outraged the British public, particularly during "Black Week" of December 1899, when the British Army suffered a series of devastating blows. Similarly, the widespread celebrations in Britain upon the relief of the beseiged towns (Ladysmith, Mafeking, etc.) were disturbed in Ireland by pro-Boer riots.
In effect it was a moment when Ireland both proved and disproved the notion that it could be a "normal" part of the United Kingdom – or of the Empire, even. The facilitation of the Boers into a respected Imperial position after the war – South Africa was soon made a self-governing dominion – encouraged Irish constitutionalist hopes. And the military successes of the Boer commandos spurred on the more militant Irish separatists.
RDF & Boer War