Radicalism (from French radical) was a political movement representing the leftward flank of liberalism between the late 18th and early 20th century. Certain aspects of the movement were precursors to a wide variety of modern-day movements, ranging from laissez-faire to social liberalism, social democracy, civil libertarianism, and modern progressivism. This ideology is commonly referred to as "radicalism" but is sometimes referred to as radical liberalism, or classical radicalism, to distinguish it from radical politics. Its earliest beginnings are to be found during the English Civil War with the Levellers and later the Radical Whigs.
During the 19th century in the United Kingdom, continental Europe and Latin America, the term radical came to denote a progressive liberal ideology inspired by the French Revolution. Radicalism grew prominent during the 1830s in the United Kingdom with the Chartists and in Belgium with the Revolution of 1830, then across Europe in the 1840s–1850s during the Revolutions of 1848. In contrast to the social conservatism of existing liberal politics, radicalism sought political support for a radical reform of the electoral system to widen suffrage. It was also associated with a variety of ideologies and policies, such as liberalism, left-wing politics, direct democracy, republicanism, modernism, atheism, secularism, antimilitarism, civic nationalism, abolition of titles, rationalism, casual clothing, redistribution of wealth and property, and freedom of the press.
