Liberalism is a political and moral philosophy based on liberty, consent of the governed, and equality before the law. Liberals espouse a wide array of views depending on their understanding of these principles, but they generally support limited government, individual rights (including civil rights and human rights), capitalism (free markets), democracy, secularism, gender equality, racial equality, internationalism, freedom of speech, freedom of the press and freedom of religion. Yellow is the political colour most commonly associated with liberalism.
Liberalism became a distinct movement in the Age of Enlightenment, when it became popular among Western philosophers and economists. Liberalism sought to replace the norms of hereditary privilege, state religion, absolute monarchy, the divine right of kings and traditional conservatism with representative democracy and the rule of law. Liberals also ended mercantilist policies, royal monopolies and other barriers to trade, instead promoting free markets. Philosopher John Locke is often credited with founding liberalism as a distinct tradition, based on the social contract, arguing that each man has a natural right to life, liberty and property and governments must not violate these rights. While the British liberal tradition has emphasized expanding democracy, French liberalism has emphasized rejecting authoritarianism and is linked to nation-building.
Leaders in the Glorious Revolution of 1688, the American Revolution of 1776 and the French Revolution of 1789 used liberal philosophy to justify the armed overthrow of royal tyranny. Liberalism started to spread rapidly especially after the French Revolution. The 19th century saw liberal governments established in nations across Europe and South America, whereas it was well-established alongside republicanism in the United States. In Victorian Britain, it was used to critique the political establishment, appealing to science and reason on behalf of the people. During 19th and early 20th century, liberalism in the Ottoman Empire and Middle East influenced periods of reform such as the Tanzimat and Al-Nahda as well as the rise of secularism, constitutionalism and nationalism. These changes, along with other factors, helped to create a sense of crisis within Islam, which continues to this day, leading to Islamic revivalism. Before 1920, the main ideological opponent of classical liberalism was conservatism, but liberalism then faced major ideological challenges from new opponents: fascism and communism. However, during the 20th century liberal ideas also spread even further—especially in Western Europe—as liberal democracies found themselves on the winning side in both world wars.
In Europe and North America, the establishment of social liberalism (often called simply "liberalism" in the United States) became a key component in the expansion of the welfare state. Today, liberal parties continue to wield power and influence throughout the world. However, liberalism still has challenges to overcome in Africa and Asia. The fundamental elements of contemporary society have liberal roots. The early waves of liberalism popularised economic individualism while expanding constitutional government and parliamentary authority. Liberals sought and established a constitutional order that prized important individual freedoms, such as freedom of speech and freedom of association; an independent judiciary and public trial by jury; and the abolition of aristocratic privileges. Later waves of modern liberal thought and struggle were strongly influenced by the need to expand civil rights. Liberals have advocated gender and racial equality in their drive to promote civil rights and a global civil rights movement in the 20th century achieved several objectives towards both goals. Continental European liberalism is divided between moderates and progressives, with the moderates tending to elitism and the progressives supporting the universalisation of fundamental institutions, such as universal suffrage, universal education and the expansion of property rights. Over time, the moderates displaced the progressives as the main guardians of continental European liberalism.
Yellow is the political colour most commonly associated with liberalism in Europe.