Alistair Lexden is the Conservative Party’s official historian.

Joe Chamberlain, in Churchill’s famous phrase, “made the weather”. By denouncing Gladstone’s Irish Home Rule Bill in 1886 and splitting the Liberal party, he changed the course of British politics. By advocating greater imperial unity through the introduction of a tariff barrier against the rest of the world in 1903, he split his later allies in the Unionist party (as the Tories were then known) and changed the course of British politics again. At the general election of 1906 the Unionists went down to their worst ever defeat in terms of seats; a tally of 157 left them in a hopeless minority, enabling the triumphant Liberals to introduce the first substantial public welfare services, for which Chamberlain himself had provided the inspiration twenty years earlier. He rarely made the political weather calm or benign.

He was an extremely difficult political colleague, “as touchy as a schoolgirl and as implacable as Juno,” in the words of one with whom he quarrelled. The great Lord Salisbury, under whom he acquired world-wide fame as Colonial Secretary in the Unionist coalition government of 1895, was struck by his inability to win hearts. “Mr Gladstone,” he said, “was much hated, but also much loved. Whoever loved Mr Chamberlain?”

Before 1886 he was a radical firebrand, widely known as “the British Robespierre”. He looked forward to the establishment of a republic in his own lifetime. He found it very distasteful to share a carriage with the Prince of Wales when the latter visited Birmingham which Chamberlain had made his impregnable political citadel, having famously transformed it into a model of good local government during a three-year period as its mayor in the 1870s. He showed his radical independence of mind by praising Disraeli’s Artisans’ Dwelling Act of 1875 which gave him powers to clear the Birmingham slums. He said that the legislation had “done more for the town of Birmingham than had been done in twenty preceding years of Liberal legislation”. Disraeli did not return the compliment. “He is no gentleman,” said Dizzy. “He has the manners of a cheese-monger.”

In June 1885 Gladstone’s daughter had a sleepless night after listening to Chamberlain’s vision of the future. “He said that none of us in the upper classes had an idea of what was coming – that it would be a new world, a complete social revolution, the land transferred to the people, all large properties broken up, class distinctions broken down… He added that parliament must have less control over the ministers – the electors ought virtually to choose a dictator for five or six years.” It was obvious to her who he thought that dictator should be.

Here then was no natural Tory ally. But from 1886 onwards Chamberlain’s Liberal Unionists and Salisbury’s Unionists had one great common cause which overrode all others: the preservation of a United Kingdom with all 32 counties of Ireland firmly within it. It has become fashionable today to laud Gladstone’s 1886 proposals for limited devolution on the grounds that, because the peace-loving Irish Nationalist MPs led by Parnell accepted them, they would have saved Britain and Ireland from the strife and bloodshed that was to follow in the Twentieth Century. Salisbury and Chamberlain – both firmly pledged to maintaining the greatness of their country – recognised that Gladstone’s scheme could provide no permanent solution. Parnell made it abundantly clear that “no man could set limits to the march of a nation,” and he possessed all the wiliness that Alex Salmond displays today in advancing the cause of Scottish nationalism.

The Unionists were right to assert that, as between unionism and nationalism, no compromise was possible. In the late 1880s and early 1890s Chamberlain and the Liberal Unionists held the balance of power at Westminster. Unable to get an intransigent Gladstone to reconsider, he committed himself permanently to an alliance with fellow Unionists of a very different political colour that kept the country together until 1922.

From the first, Chamberlain sought to invest the Unionist alliance with a much wider purpose. Speaking on 9 April 1886, he called for the establishment of legislatures in Scotland, Wales, England and Ireland (with perhaps a further one for Ulster) subordinate to a reconstituted Westminster as part of a great scheme that should be extended in due course to the colonies and so “draw tighter the bonds which unite us and bring the whole Empire into one federation”.

The “British Robespierre” was transformed into the most determined imperialist in front-rank politics, though without ever acquiring affection for the monarchy. He now put forward a new vision without altogether abandoning the old one that had shocked poor Miss Gladstone. After Britain’s unexpectedly difficult victory in the Boer War in 1902, he moved swiftly into the most remarkable political campaign of his career. It involved reversing Robert Peel’s victory for free trade and cheap food which had split the Tory party sixty years earlier.

Britain and the Empire, he proclaimed, must form a common market behind a tariff wall as a prelude to ever closer political union. He looked forward to the day when it would be possible to form “a real council of the Empire to which all questions of imperial interest might be referred. Such a council would be at first merely advisory; but its object would not be completely secured until it had attained executive functions and perhaps some legislative powers.” In his grand scheme, new import duties would contribute significantly to paying for the welfare state in Britain to which he also looked forward, but which was not taken in hand until the Liberal party that he had deserted achieved their triumph in  1906.

No one ever excelled Chamberlain in the dark arts of political organisation. He had a genius for them. All 12 Birmingham seats remained loyal to him and his Unionist creed until 1945 with Labour consistently defeated in every contest – and the word Conservative was never heard in the city. The Tariff Reform League which he founded in 1903 had plentiful funds, massive press support and the enthusiastic backing of Unionists in the constituencies. Yet, heavily outnumbered though they were, the Unionist opponents of tariffs fought Chamberlain tooth and nail, precipitating the dire defeat of 1906.

He by no means despaired. The band of 157 Unionists returned in 1906 were almost to a man committed to tariff reform. He saw no reason why the cause should not ultimately triumph. Within months, however, a massive stroke left him a hopeless cripple unable to attend the Commons. Though tariffs were eventually reintroduced by his younger son Neville in the 1930s, no-one sustained effectively the broader vision of which they were part. “I care only,” he wrote on 21 September 1903, “for the great question of imperial unity.” His fellow Unionists did not take the torch from him.

He was an extraordinarily unusual phenomenon in British politics. “The holding of strongly patriotic and national opinions in foreign affairs, combined with extreme radical opinions upon internal matters, made it difficult [for him] to act with anybody for long,” as a friend put it early in his career. He became an indispensable figure in a remarkable Unionist alliance, but produced tensions within it that brought it low in 1906.

On the morning of 2 July 1914 his wife read The Times to him as usual. The leading article was on the murder of the Archduke Franz Ferdinand. According to his admiring biographer, Julian Amery, “Mrs Chamberlain began to read it to him, but he stopped her as if it were more than he could bear. He saw clearly that the world was on the brink of war.” He died later in the day. Burial in Westminster Abbey was declined by his family in favour of a Unitarian church in Birmingham. Amery concludes, “He was true to himself in this last gesture, as throughout his life.”