The main outcome of the Congress of Vienna in 1815 was the restoration of peace and the re-establishment of a balance of power in Europe following the Napoleonic Wars. The Congress, attended by major European powers such as Austria, Prussia, Russia, and Great Britain, aimed to prevent future conflicts through diplomacy. It led to the redrawing of territorial boundaries, the restoration of monarchies, and the creation of the Concert of Europe, a diplomatic framework that sought to maintain stability and manage international relations. Ultimately, the Congress laid the groundwork for European diplomacy in the 19th century.