Whilst the Congress was ongoing, on 1 March Napoleon returned to France from exile, won the French Army to his cause and deposed the Bourbon king, Louis XVIII. The great powers mobilised armies against him, including an Anglo-Dutch-Belgian force under the Duke of Wellington and a Prussian Army under Gebhard Leberecht von Blücher. In the Waterloo Campaign, Napoleon sought to defeat these two armies before reinforcements could arrive from Austria and Russia.
