The Franks assisted in the repulsion of Adelchis, but, in turn, attacked Benevento's territories several times, obtaining small gains, notably the annexation of Chieti to the duchy of Spoleto.

In 814, Grimoald IV made vague promises of tribute and submission to Louis the Pious, which were renewed by his successor Sico.

The Beneventan dukes employed seal rings to confirm documents, just like the Lombard kings, and the princes may have continued to use them into the ninth century.

[1] In the following century despite the continuing hostility of the Frankish sovereigns, Benevento reached its apex, imposing a tribute on Naples and capturing Amalfi under Duke Sicard.

The crisis was aggravated by the beginning of Muslim ravages, the first Saracens having been called in by Radelchis and subsequently Siconulf in their decade-long war.

In 1022, Henry II, Holy Roman Emperor conquered both Capua and Benevento, but returned to Germany after the failed siege of Troia.

Successively The Normans arrived in the Mezzogiorno in these years, and Benevento then acknowledged to be in papal suzerainty, was only an off-and-on ally.

Finally, in 1081, Guiscard returned the title to the papacy with little but the city remaining of the once-great principality which had determined the direction of South Italian affairs for generations.