The ideology that sought to usurp traditional monarchies during the Enlightenment is liberalism. It promoted ideals such as individual rights, freedom, and equality, opposing the absolute power of monarchs. Thinkers like John Locke and Voltaire argued for government based on consent and advocated for social contracts that protect individual liberties. This ideology challenged existing hierarchies and contributed to revolutions, fundamentally reshaping governance in Europe and beyond, and laid the groundwork for modern democratic systems.