Liberalism (from the Latin liberalis) is the belief in the importance of liberty and equal rights. Liberals espouse a wide array of views depending on their understanding of these principles, but generally, liberals support ideas such as constitutionalism, liberal democracy, free and fair elections, human rights, capitalism, and freedom of religion. These ideas are widely accepted, even by political groups that do not openly profess a liberal ideological orientation. Liberalism encompasses several intellectual trends and traditions, but the dominant variants are classical liberalism, which became popular in the eighteenth century, and social liberalism, which became popular in the twentieth century.
Liberalism first became a powerful force in the Age of Enlightenment, rejecting several foundational assumptions that dominated most earlier theories of government, such as nobility, established religion, absolute monarchy, and the Divine Right of Kings. The early liberal thinker John Locke, who is often credited for the creation of liberalism as a distinct philosophical tradition, employed the concept of natural rights and the social contract to argue that the rule of law should replace absolutism in government, that rulers were subject to the consent of the governed, and that private individuals had a fundamental right to life, liberty, and property.
The revolutionaries in the American Revolution and the French Revolution used liberal philosophy to justify the armed overthrow of tyrannical rule. The nineteenth century saw liberal governments established in nations across Europe, Latin America, and North America. Liberal ideas spread even further in the twentieth century, when liberal democracies triumphed in two world wars and survived major ideological challenges from fascism and communism. Today, liberalism in its many forms remains as a political force to varying degrees of power and influence on all major continents.