In occasion of the Papal conclave that took place in Viterbo in 1269, the Church laid a claim on the territory. In 1235, Pope Gregorius IX included the Fortress of Lariano in the Castellanie, a group of castles run by officials under the Church’s mandate.

When Pope Clement IV died in 1268, Ricciardello Annibaldi took possession of the castle and for this reason, under pressure by the College of Cardinals, the troops of Velletri attacked Annibaldi, in the name and on behalf of the Church, but were defeated.

It was, indeed, the Colonna family who conquered the territory where they remained until the Antipope Clement VII handed it over to the Orsini family. After fierce fighting, the fortress was returned to the Colonna family but by a surprise attack in 1412, Teobaldo Annibaldi became the new landowner of Lariano.

In 1417, Oddone Colonna, appointed Pope Martino V, conferred the fief to his family who ruled it once again until his death (in 1431), when Pope Eugene IV abolished the privileges granted by the previous Pope. Furious battles broke out between the Church and the Colonna family, who were defeated only by Velletri’s soldiers led by Paolo Annibaldi della Molara; in 1436, after the castle had been burnt and destroyed, Pope Eugene IV surrendered the area to Velletri as a sign of gratitude for the support received.

From then onwards, Lariano lost its independence and became a community of Velletri until 1967 when it became commune, which later achieved a substantial population and economical growth.

Most of the territory of Lariano comes under the Parco Regionale dei Castelli Romani (Regional Park of the Castelli Romani) and the town’s surrounding woods are a good opportunity for interesting excursions during the right seasons.