Nationalism in Ireland is one of the oldest political traditions of that country, one that acquired new effectiveness and influence in the late nineteenth century. Between 1874 and 1914, British and Irish politicians elaborated and debated various schemes of constitutional reform, with a view to transforming the unitary parliamentary state into either a federation or a union with a special devolved parliament for the whole of Ireland. The latter went under the name of Home Rule, because it was about giving the Irish control of their domestic affairs without terminating the 1800 Union with Britain. Home Rule fell far short of independence, or even what later came to be known as “Dominion Status.” Yet it bitterly divided British and Irish political opinion for two generations and brought the country to the brink of civil war by 1912. Passed, but not implemented, in 1914 (because of Ulster’s strong opposition), Home Rule was then revised and passed again by the UK parliament in 1920. At that stage, however, it was “too little, too late” for the nationalists, who demanded full independence and were prepared to fight for it (in the War of Independence of 1919-21 and the Civil War of 1922-3). Was Home Rule the great missed opportunity to avoid such bloodshed and long-term unrest? This article concludes that a peaceful solution would have been possible, had it not been for the polarization of the debate and the militancy fomented by London-based leaders, who realised that Home Rule elicited fury and militancy among both English and Scottish imperialists while, at the same time, it galvanised the Liberals into frenzies of selfless idealism. That Gladstone, Salisbury, Balfour, Chamberlain, Asquith, Lloyd George, Churchill and Bonar Law were able to capitalise so much from the issues raised by the “Irish Question” suggests that the latter went unanswered because it was, ultimately, a “British Question”—or a question about which the British people had very strong views.