The historical significance of the Battle of Waterloo, fought on June 18, 1815, lies in its decisive role in ending the Napoleonic Wars and the reign of Emperor Napoleon Bonaparte. The battle pitted British-led Allied forces against Napoleon's army and culminated in a critical defeat for the French. As a result, Napoleon was exiled to Saint Helena, and the victory restored a balance of power in Europe, paving the way for a period of relative peace known as the Concert of Europe and shaping future international relations.