In the 8th century (circa 725) the Umayyad forces conquered the area, but the stronghold was destroyed by Charles Martel in his 737 campaign across Septimania, almost depopulating the region.

The Gallo-Roman and Gothic nobility allied with the Andalusian military kept the position until 752, when Pepin the Short tipped the scale in favour of the Franks, who conquered Septimania.

The diocese was removed to Substantion (Sextantio), but Bishop Arnaud (1030–1060) returned it, rebuilt the destroyed sanctuary and constructed a bridge to link Maguelone to the "new district" of Villeneuve.

[4] The bishop, as well as the King of Aragon and the Count of Toulouse, authorized the coinage of Arabic money, not intended for circulation in Maguelonne, but to be sold for exportation to the merchants of the Mediterranean.

[5] A sentimental and chivalric romance of the high-born Miguelonne and Pierre, the son of the King of Provence, who recognized each other in their old age after many heartbreaking separations, inspired a verse: Epistle by Clément Marot.