After the defeat of Napoleon at the Battle of Waterloo and the advance on Paris by the Coalition armies during the months of June and July 1815, although they besieged and took some towns and fortresses as they advanced, they bypassed many of them and detached forces to observe and reduce them. The last of the French fortresses did not capitulate until September of that year.

The Hundred Days, also known as the War of the Seventh Coalition, marked the period between Napoleon's return from eleven months of exile on the island of Elba to Paris on 20 March 1815 and the second restoration of King Louis XVIII on 8 July 1815. This period saw the War of the Seventh Coalition, and includes the Waterloo Campaign and the Neapolitan War as well as several other minor campaigns. The phrase les Cent Jours was first used by the prefect of Paris, Gaspard, comte de Chabrol, in his speech welcoming the king back to Paris on 8 July.