Winston Churchill called Chamberlain "a splendid piebald: first black, then white, or, in political terms, first fiery red, then true blue".
That is the conventional view of Chamberlain's politics – that he became gradually more conservative, beginning to the left of the Liberal party and ending to the right of the Conservatives.
An alternative view is that he was always a radical in home affairs and an imperialist in foreign affairs, and that those stances were not in great conflict with each other – with both he rejected "laissez-faire capitalism".
For instance, after leaving the Liberals he remained a proponent of workmen's compensation and old-age pensions.

Historian J. A. R. Marriott says that in the 1870–1905 period Chamberlain was:
of all English statesman, the most representative and one of the most influential.
Firmly convinced of the merits of parliamentary democracy, an ardent social reformer, though opposed to social revolution, above all, a whole-hearted believer in the Imperial mission of the British race, Chamberlain preeminently embodied the most vital of the most characteristic ideas of that epoch....[in Birmingham he was] A strong advocate of municipal enterprise, he stimulated the Corporation to purchase the gas-works, the water-works, the sewage farm, and by extensive scheme of slum clearance and rehousing, he transformed the outward aspect of the city is his adoption....[Once in Parliament,] from the [Liberal] Party point of view Chamberlain's support became increasingly indispensable but it was rendered with increasing reluctance.

Historian Dennis Judd says:
There is something so elemental and, in a way, timeless about the meteoric rise of Chamberlain: from his modest London Unitarian background, via his brilliant industrial and commercial career in Birmingham, to a position of almost supreme political power, where he could (and did) make and break the two major parties of late-Victorian and Edwardian England, destroy the immediate prospect of Irish Home Rule, reshape the British Empire, press for a restructuring of British economic policies and bestride the international stage as significantly as Rhodes or Bismarck.

Historian R. J. A. Adams writes: "A great patriot who burned to guarantee his country's future, Chamberlain's brilliance and impatience guaranteed that he would be judged a political messiah to some, but an unstable destroyer to many more."

A. J. P. Taylor states:
Joseph Chamberlain was the greatest force in British politics between the decline of Gladstone and the rise of Lloyd George.
He was a pioneer in social reform and municipal enterprise.
He defeated Irish Home Rule.
He inspired a new era in British Imperialism and directed its triumph in the Boer War... He challenged the accepted dogmas of Free Trade and launched the movement for Tariff Reform, which was to transform British economic life a generation after his death.
 Despite these achievements, nothing went right with him.
 He stands pre-eminent as a Splendid Failure... Chamberlain, it seems, was successful only in destruction, bringing ruin first to the Liberal, and then to the Unionist, party.
Winston Churchill called Chamberlain "a splendid piebald: first black, then white, or, in political terms, first fiery red, then true blue". That is the conventional view of Chamberlain's politics – that he became gradually more conservative, beginning to the left of the Liberal party and ending to the right of the Conservatives. An alternative view is that he was always a radical in home affairs and an imperialist in foreign affairs, and that those stances were not in great conflict with each other – with both he rejected "laissez-faire capitalism". For instance, after leaving the Liberals he remained a proponent of workmen's compensation and old-age pensions.
Historian J. A. R. Marriott says that in the 1870–1905 period Chamberlain was:
of all English statesman, the most representative and one of the most influential. Firmly convinced of the merits of parliamentary democracy, an ardent social reformer, though opposed to social revolution, above all, a whole-hearted believer in the Imperial mission of the British race, Chamberlain preeminently embodied the most vital of the most characteristic ideas of that epoch....[in Birmingham he was] A strong advocate of municipal enterprise, he stimulated the Corporation to purchase the gas-works, the water-works, the sewage farm, and by extensive scheme of slum clearance and rehousing, he transformed the outward aspect of the city is his adoption....[Once in Parliament,] from the [Liberal] Party point of view Chamberlain's support became increasingly indispensable but it was rendered with increasing reluctance.
Historian Dennis Judd says:
There is something so elemental and, in a way, timeless about the meteoric rise of Chamberlain: from his modest London Unitarian background, via his brilliant industrial and commercial career in Birmingham, to a position of almost supreme political power, where he could (and did) make and break the two major parties of late-Victorian and Edwardian England, destroy the immediate prospect of Irish Home Rule, reshape the British Empire, press for a restructuring of British economic policies and bestride the international stage as significantly as Rhodes or Bismarck.
Historian R. J. A. Adams writes: "A great patriot who burned to guarantee his country's future, Chamberlain's brilliance and impatience guaranteed that he would be judged a political messiah to some, but an unstable destroyer to many more."
A. J. P. Taylor states:
Joseph Chamberlain was the greatest force in British politics between the decline of Gladstone and the rise of Lloyd George. He was a pioneer in social reform and municipal enterprise. He defeated Irish Home Rule. He inspired a new era in British Imperialism and directed its triumph in the Boer War... He challenged the accepted dogmas of Free Trade and launched the movement for Tariff Reform, which was to transform British economic life a generation after his death.  Despite these achievements, nothing went right with him.  He stands pre-eminent as a Splendid Failure... Chamberlain, it seems, was successful only in destruction, bringing ruin first to the Liberal, and then to the Unionist, party.
Joseph Chamberlain