The Declaration of Independence asserts that governments “deriv[e] their just powers from the consent of the governed,” distilling concepts invoked by Locke and earlier English political reformers. For the English-speaking world, however, the germ of that concept can be found in Magna Carta.
At the time, feudal barons could be required to provide what was known as “scutage,” essentially a fee in lieu of personal service typically used to hire mercenaries to fight the king’s wars. Other aid levies were also common. King John, however, was perceived as abusing the system, imposing unusually high levies and doing so even in the absence of war.
Magna Carta introduced a revolutionary innovation: the idea that the power to tax was in some way limited by general consent. Still, it being the year 1215, there were some loopholes:
No scutage not aid shall be imposed on our kingdom, unless by common counsel [alt. "general consent"] of our kingdom, except for ransoming our person, for making our eldest son a knight, and for once marrying our eldest daughter; and for these there shall not be levied more than a reasonable aid…