The existence of agropoli dates from the fifth century AD, not finding any mention in the writers and the documents before to that time. Its name, which comes from «acros» and «polis», means «High town», and it suggests, in keeping with the tradition, of Greek origin; and in fact it would have been built by the Byzantine Greeks, when led by Belisario, they occupied the Lucania, after 535.Its location on a hill, which on one hands down to the sea and the other side overlooking the plains nearby, must have seemed to the victorious Greeks well suited to oversee the lands.

A popular legend tells that to agropoli landed St. Paul in his journey from Reggio to Pozzuoli to spread Christianity, and that, two children of the place, converted, were stoned in a place that still takes the name of the saint, and that they were buried in the place of holy water, in the municipality of Laureana, where there is still a small church.It is said that St. Francis preached to agropoli in 1222 and in that place was built a monastery. The oldest document, which referred to Agropoli, is the letter in which Gregorio the pope in 599 instructed Felice, bishop of Agropoli, to visit the churches of Velia, Blanda and Bussento.

One of the most famous events in the history of agropoli is the occupation of the city by the Saracens. After being beaten at the Vesuvius by the Prince of Salerno, they took refuge, fortifying, on the hill, almost impregnable.From there the Saracens infested for many years the whole province of Salerno, spreading terror and desolation, until they were defeated in1028 by Guaimario, Prince of Salerno, and Pandolfo, Prince of Capua, and they went away.

We don't know which age the house had gone to Sanseverino family, principles of Salerno. We only know that with privilege of Ferdinand I of Aragon, in 1463, it was confermed.In 1505 the castle of Agropoli and his house belonged to Rodrigo d'Avalos, Marquis of Vast, that had driven the French from Salerno.Occurred then peace between France and Spain, it was agreed that all the lands were returned to the barons and so Agropoli returned to Sanseverino and the city was part of the barony of Cilento, whose headquarters was Rocca Cilento.Later Agropoli suffered for the pirates. Lenormant says that during the cruise made in 1535 by the pirate Barbarossa along the coasts of the kingdom of Naples, Agropoli was taken and 500 of its inhabitants were enslaved.

The Ventimiglia reports that June 29, 1629 the Turks of Biserta, with seven galleys and two brigs, gave the night the assault on the city. Penetrated the barbarians, the people were able to barely take shelter in the castle. Many citizens from neighboring countries flocked to fight invaders, camping at the church of Our Lady of the plain.It was a Saturday, and many people were in the market at the Church of St. Mary of the martyrs.

Spread the news, Bernardo Rigno, a Spanish soldier, called to arms and a lot of people went down to Agropoli.The Turks, about 700, were divided into three armies: one attacked the city, another attacked the castle, the third attacked the 2000 people from Cilento.

The Turks found shelter on their galleys. After the felony of Sanseverino in 1552, the land of agropoli was sold to John D'Ayerbo D'Aragona in 1553.In that period Agropoli lived the great famine of 1564 and the citizens, starving, having learned that the bishop of Capaccio possessed much grain in warehouses, they violently penetrated there and seized about 600 tomoli.

Later the fief of agropoli was sold to Nicola Grimaldi, Prince of Salerno and after to Domizio Arcella Caracciolo. In 1626 it was property of Tommaso Filomarino prince of Roccadaspide and after it belonged to Giulio Mastrillo who sold it to Cesarano Zattera. In 1656 Agropoli suffered the great plague that destroyed 62 families.In 1746 Agropoli belonged to Sanfelice from Laureana.The castle had under him seven hamlets, such as Ogliastro and Eredità. These villages were built by the inhabitants of Agropoli when their country was occupied by the Saracens.