Vallemaio is part of the Land of St. Benedict, which is the area of influence by the Abbey of Monte Cassino, at its greatest extent, when it reached the Tyrrhenian Sea through the Garigliano river valley. The river was an important road link between the Abbey and the sea.
The origin is traced to the donation of land to the monastery in 744 by the Lombard Gisulfo II, Duke of Benevento.
The monks had total autonomy and control management over this donation and strove immediately to arrange the district with the reclamation of the area of marshy land reclamation in the vicinity of the Rapido River and strategic construction in the district of small monasteries, the cells. Each part of the estate to become a cell was called a ‘curtis’. Each curtis had to be economically independent, in line with the spirit of the Benedictine Rule.