It renewed the use of the Congress System which sought to stabilize European international relations at the time and pledged each signatory to a military alliance that ultimately aimed to crush any recurrence of revolutionary outbreaks like those that led to the French Revolution if they occurred anywhere in Europe. The quadruple alliance lasted until 1818,[1][2][3] by which time the restoration of the Bourbon monarchy enabled France - now a constitutional monarchy ruled by King Louis XVIII - to join the Quadruple Alliance, turning it into the Quintuple Alliance.