What could stop the monarchies of Europe?

The people of those monarchies overthrowing them such as the French Revolution, which ironically was replaced by another monarchy.

Or even the government itself finding the monarchy unfit to lead to country which this is just hypothetical but when the British government was still a monarchy the Parliament could have overthrown the monarchy.

Explanation:

john locke is most associated with the idea of consent of the governed which is the idea that the government is only valid if it has the consent of the people who are being governed.

hope this

a phrase from a poem by ralph waldo emerson about the battle of lexington and concord. emerson's words read, “here once the embattled farmers stood / and fired the shot heard round the world.”