What is the Concert of Europe?

• A. An informal system to maintain the balance of power and prevent major conflicts in Europe.
• B. A formal alliance treaty signed by all major powers.
• C. A European economic union.
• D. A military coalition against Russia.

Answer: (A)

The Concert of Europe is an informal system of great-power diplomacy designed to preserve the balance of power in Europe and prevent large-scale wars after the Napoleonic era. After 1815, Britain, Austria, Russia, Prussia, and later France kept contact through regular congresses and consultations, using consensus and diplomatic mediation to manage crises, restore the old order when needed, and suppress revolutionary movements without binding military pacts or a formal treaty.

This is why the description fits best: it emphasizes an informal, coordinated approach among major powers aimed at maintaining peace and the balance of power, rather than a formal alliance, an economic union, or a specific military coalition against a particular country.