Procida suffered numerous Saracen incursions; the Visigoths of Alarico, the Vandals of Genserico brought destruction to the Campanian coasts. The inhabitants of nearby Miseno were forced to take refuge in Procida and so the Count put the whole territory under the jurisdiction of the island. The name Monte di Procida derives from this incident. Around the 10th century, the first Benedictine installations were established in the cenoby of Santa Margherita Vecchia and later in Marina Chiaiolella.

Following the continuous Saracen raids, the village of Terra Murata became stronger, it was then denominated Terra Casata: around the 11th century, the abbey of San Michele Arcangelo was built by the Benedictine monks.
In the 12th century, Procida and Monte di Procida became fiefs of the Normans. Feudal lords of the island were the "da Procidas" who included the famous Giovanni da Procida, hero of the Sicilian vespers, the first, great "Signore" of the island. The residence of the family da Procida is said to be at Terra Murata.

In 1340, Procida, Monte di Procida and the small islet of Vivara were purchased by the family Cossa which, in the following century, was followed by the dynasty of the Aragonese.
In 1529, king Karl the fifth of Hapsburg entrusted Procida to the d'Avalos. One prominent character was Innico d'Avalos, who brought notable changes to the island and, in particular, to the inhabited village of Terra Murata to better protect the inhabitants from the frequent Saracen raids.
The building of the Castello d'Avalos was created by him and also the surrounding walls (accessible only by going through the still visible iron portal, situated near the belvedere of two canons) which he denominated the village of Terra Casata, in the suburb of Terra Murata (earth surrounded by walls).
The family d'Avalos, following a forfeiture, was succeeded by the Bourbons in the 18th century.
Since then, Procida and its history merged together with the history of the kingdom of Naples.
The island became a fief of hunting, "a reserve for imperial hunting" and the Castello d'Avalos was turned first into a royal palace and subsequently into Bagno Penale.
The list of the guests who have come to the island is rich in illustrious names linked to the fascist regime: the viceroy of Ethiopia and Albania, some ministers of the Duce and prince Junio Valerio Borghese, the unforgettable Commander of the X Mas (Decima Mas naval unit).

But the history of Procida is also the history of its marine. The first inhabitants of the island certainly came from the sea.
Unlike the other two islands in the gulf, the procidans have found a source of prosperity and wealth in the sea. Skilled sailors but also clever shipowners who at the end of the 19th century represented one sixteenth of the entire Italian merchant fleet. Even if the advent of vapor navigation has brought an end to this predominance of the Procidan naval industry, it has not stopped the naval vocation of the island that has continued and continues to produce brave commanders and chief engineers who are formed in the glorious Nautical Institute “F. Caracciolo”.