The gradual collapse of the Roman empire due to the increasing Germanic invasions of the 5th century, sent the city into a period of decline. In 451 CE, the city was threatened by the army of Attila the Hun, which had pillaged Treves, Metz and Reims. The Parisians were planning to abandon the city, but they were persuaded to resist by Saint Geneviève (422–502). Attila bypassed Paris and attacked Orléans. In 461, the city was threatened again by the Salian Franks led by Childeric I (436–481). The siege of the city lasted ten years. Once again, Geneviève organized the defense. She rescued the city by bringing wheat to the hungry city from Brie and Champagne on a flotilla of eleven barges.

In 486, Clovis I, King of the Franks, negotiates with Saint Genevieve the submission of Paris to his authority. Burial of Saint Genevieve atop the hill on the left bank which now bears her name. A basilica, the Basilique des Saints Apôtres, is built on the site and consecrated on 24 December 520. It later becomes the site of the Basilica of Saint-Genevieve, which after the French Revolution becomes the Panthéon. She became the patron saint of Paris shortly after her death.