Le ralliement du 5e d’infanterie de ligne à l’Empereur, le 7 mars 1815, de Charles Auguste Guillaume Steuben
The Hundred Days, sometimes known as the Hundred Days of Napoleon or Napoleon’s Hundred Days for specificity, marked the period between Emperor Napoleon I of France’s return from exile on Elba to Paris on 20 March 1815 and the second restoration of King Louis XVIII on 8 July 1815 (a period of 111 days). This period saw the War of the Seventh Coalition, and includes the Waterloo Campaign and the Neapolitan War. The phrase les Cent Jours was first used by the prefect of Paris, Gaspard, comte de Chabrol, in his speech welcoming the King.
Napoleon returned while the Congress of Vienna was sitting. On 13 March, seven days before Napoleon reached Paris, the powers at the Congress of Vienna declared him an outlaw, and on 25 March, five days after his arrival in Paris, Austria, Prussia, Russia and the United Kingdom, members of the Seventh Coalition, bound themselves to put 150,000 men each into the field to end his rule. This set the stage for the last conflict in the Napoleonic Wars, the defeat of Napoleon at the Battle of Waterloo, the restoration of the French monarchy for the second time and the permanent exile of Napoleon to the distant island of Saint Helena, where he died in May 1821.