In the fields of history and political science, a revolution is a radical change in the established order, usually the established government and social institutions. Typically, revolutions take the form of organized movements aimed at effecting change—economic change, technological change, political change, or social change. The people who start revolutions have determined the institutions currently in place in society have failed or no longer serve their intended purpose. Because the objective of revolutions is to upturn established order, the characteristics that define them reflect the circumstances of their birth.

Revolutions are born when the social climate in a country changes and the political system does not react in kind. People become discouraged by existing conditions, which alters their values and beliefs. Over the course of history, philosophers have held different views as to whether revolution is a natural occurrence in a changing society, or whether it indicates social decay. The Greek philosopher Aristotle linked revolution to a number of causes and conditions, but largely to the desire for equality and honor. Plato linked revolution to social decay. He believed that revolutions occur when institutions, such as the Church or the State, fail to instill in society a system of values and a code of ethics that prevent upheaval.

Throughout the Middle Ages, Europeans generally did what they could to prevent revolution and preserve the established order. The Church maintained the authority in medieval times, and it aimed to preserve stability in society at all costs. Sometime during the Renaissance, however, the concept of revolution began to change. People began to believe change was necessary for society to progress.

Between 1450 and 1750, philosophical and political ideas were changing rapidly throughout the world. The Renaissance, the Scientific Revolution, and the Protestant Reformation all took place during this time period, and people expanded their worldviews as they gained knowledge of new concepts and accepted new ideas. At this time in Europe, most countries had absolute monarchies, and people began to question the power of absolute governments. As their discontent grew, their questions turned to protests. A wave of revolutions took place in the 1700s, an era commonly known as the Age Enlightenment—revolutions in France, in Latin America, and in the American colonies. In all these countries, the revolutions not only changed the political systems and replaced them with new ones, but they altered public belief and brought about sweeping changes in society as a whole.