The abolition of monarchy has occurred throughout history, either through revolutions, coups d'état, wars, or legislative reforms (such as abdications). The founding of the Roman Republic is a noteworthy example and became part of the nation's traditions including as justification for the assassination of Julius Caesar. The twentieth century saw a major acceleration of this process, with many monarchies violently overthrown by revolution or war, or else abolished as part of the process of decolonisation. By contrast, the restoration of monarchies is rare in modern times, with only two major examples, Spain and Cambodia.
An early example of the abolition of a monarchy in modern times occurred in 1649 with the overthrow of the English monarchy by the Parliament of England and its armed forces under leaders such as Oliver Cromwell. 1660 saw a monarchical restoration - though in a more limited form moderated by a more independent Parliament.
Anti-monarchism in the United States developed out of the gradual process of revolution that began as early as 1765, as colonists resisted the Stamp Act through boycott and the expulsion and condemnation of royal officials. While subjects of Great Britain (a union of the Kingdom of England with the Kingdom of Scotland), the colonists of British North America enjoyed a level of autonomy which increasingly clashed with royal and Parliamentary authority which did not consult colonial needs. With the Declaration of Independence in 1776, the most violent wave of anti-monarchical protest began, with the systematic destruction of the relics and symbols of monarchy. Examples can be found in the toppling of the equestrian statue of George III on Bowling Green in New York City (9 July 1776). Monarchic loyalists were particularly affected by partisan attacks or harassment, with tens of thousands leaving for Canada, Britain, and other colonies. Wealth or property which remained was typically confiscated.Thomas Paine, the famous author of the revolutionary pamphlet "Common Sense", urged the colonists to finance the revolutionary war through this means. Even today, very few artifacts depicting the British monarchy from the colonial period can be found in the United States. However, not all anti-British or anti-Loyalist sentiment equated to anti-monarchism. The normalcy of having a King at the head of a polity had strong roots in much political thought (Machiavelli, Hobbes) and in religious doctrine (see for example 1 Samuel 8:6-9. Some Americans saw the presidency in monarchical terms.