<P> A genuine two - party system began to emerge, with the accession to power of William Pitt the Younger in 1783 leading the new Tories, against a reconstituted "Whig" party led by the radical politician Charles James Fox . </P> <P> The two party system matured in the early 19th century era of political reform, when the franchise was widened and politics entered into the basic divide between conservatism and liberalism that has fundamentally endured up to the present . The modern Conservative Party was created out of the "Pittite" Tories by Robert Peel, who issued the Tamworth Manifesto in 1834 which set out the basic principles of Conservatism; - the necessity in specific cases of reform in order to survive, but an opposition to unnecessary change, that could lead to "a perpetual vortex of agitation". Meanwhile, the Whigs, along with free trade Tory followers of Robert Peel, and independent Radicals, formed the Liberal Party under Lord Palmerston in 1859, and transformed into a party of the growing urban middle - class, under the long leadership of William Ewart Gladstone . The two party system had come of age at the time of Gladstone and his Conservative rival Benjamin Disraeli after the 1867 Reform Act . </P> <P> Although the Founding Fathers of the United States did not originally intend for American politics to be partisan, early political controversies in the 1790s saw the emergence of a two - party political system, the Federalist Party and the Democratic - Republican Party, centred on the differing views on federal government powers of Secretary of the Treasury Alexander Hamilton and James Madison . However, a consensus reached on these issues ended party politics in 1816 for a decade, a period commonly known as the Era of Good Feelings . </P> <P> Partisan politics revived in 1829 with the split of the Democratic - Republican Party into the Jacksonian Democrats led by Andrew Jackson, and the Whig Party, led by Henry Clay . The former evolved into the modern Democratic Party and the latter was replaced with the Republican Party as one of the two main parties in the 1850s . </P>

How can the two party dominance in much of us history best be explained