The Concert of Europe was a general consensus among the great powers of 19th-century Europe to maintain the European balance of power, political boundaries, and spheres of influence. Never a perfect unity and subject to disputes and jockeying for position and influence, the Concert was an extended period of relative peace and stability in Europe following the Wars of the French Revolution and Napoleonic Wars which had consumed the continent since the 1790s. There is considerable scholarly dispute over the exact nature and duration of the Concert. Some scholars argue that it fell apart nearly as soon as it began in the 1820s when the great powers disagreed over the handling of liberal revolts in Italy, while others argue that it lasted until the outbreak of World War I and others for points in between. For those arguing for a longer duration, there is generally agreement that the period after the Revolutions of 1848 and the Crimean War (1853-1856) represented a different phase with different dynamics than the earlier period.
The beginnings of the Concert of Europe, known as the Congress System or the Vienna System after the Congress of Vienna (1814–1815), was dominated by the five great powers of Europe: Austria, France, Prussia, Russia, and the United Kingdom. Initially envisioning regular Congresses among the great powers to resolve potential disputes, in practice, Congresses were held on an ad hoc basis and were generally successful in preventing or localizing conflicts. The more conservative members of the Concert of Europe, members of the Holy Alliance (Russia, Austria, and Prussia), used the system to oppose revolutionary and liberal movements and weaken the forces of nationalism. The formal Congress System fell apart in the 1820s but peace between the Great Powers continued and occasional meetings reminiscent of the Congresses continued to be held at times of Crisis.
The Concert faced a major challenge in the Revolutions of 1848 which sought national independence, national unity, and liberal and democratic reforms.