Tax resistance, the practice of refusing to pay taxes that are considered unjust, has probably existed ever since rulers began imposing taxes on their subjects. It has been suggested that tax resistance played a significant role in the collapse of several empires, including the Egyptian, Roman, Spanish, and Aztec. Many rebellions and revolutions have been prompted by resentment of taxation or had tax refusal as a component. Examples of historic events that originated as tax revolts include the Magna Carta, the American Revolution, and the French Revolution.