Papal Suzerainty
In 763, the duke Stephen II switched his allegiance from Constantinople to Rome, putting Naples under papal suzerainty. Already during the reign of the imperially appointed John I (711- ca 719), the papacy had come to the duke's aid against the Lombards, while Byzantine assistance seemed remote. Stephen II's reign is considered a period of transition in the history of Naples: it moved away from the iconoclastic East and towards the papal West. The Byzantine Greeks were soon to become as much a threat to the Neapolitans as the Lombards.
Sometime around the beginning of the ninth century, the dukes began striking coinage with Latin inscriptions, as Latin replaced Greek in official usage. Saint Januarius replaced the emperor on the coins. Acts were still dated by the imperial reign, but the emperor was of no consequence in regular Neapolitan affairs. In 812, when Leo III the Isaurian called for the fleet of the entire ducatus to aid the Byzantine admiral in combatting the Saracen pirates preying on Sicily, Duke Anthimus could ignore the order; only Amalfi and Gaeta responded with contingents. Apparently, the Neapolitans felt themselves practically independent already and their underlings felt themselves independent of Naples.
The duchy was not yet hereditary; in 818, the patrician of Sicily appointed Theoctistus without imperial approval. He revoked this appointment, and appointed one Theodore II in 821, but he was chased from the city the same year in favour of the elected Stephen III. This Stephen first began to mint pieces with his own initials on them and not those of the Eastern Emperor.
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