The significant military engagement that took place in 1815, effectively ending the Napoleonic Wars, was the Battle of Waterloo. This decisive battle saw the forces of the Duke of Wellington and Marshall Blücher join to defeat Napoleon Bonaparte's army, leading to his final abdication. The defeat marked the end of over two decades of conflict involving various European powers and established a new order in Europe, emphasizing a balance of power. Following Waterloo, Napoleon was exiled to Saint Helena, and the Congress of Vienna aimed to restore stability and prevent future widespread conflict in Europe.