Toward the end of the 15th century the Ottoman Turks expanded their control of the Mediterranean westwards and became a dominant maritime power in the region.
In the first decades of the 16th century Turkish corsairs in galleys and fustas often rowed by Christian slaves began attacking villages around the Corsican coastline.
In 1531, the Genoese Bank of Saint George sent two extraordinary representatives, Paolo Battista Calvo and Francesco Doria, to inspect the fortifications defending the island from the Barbary corsairs.
The work began under the supervision of two new Genoese representatives, Sebastiano Doria and Pietro Filippo Grimaldi Podio.
The towers performed three functions: they defended the villages and ports, they acted as landmarks for navigators and they allowed news of an attack to be rapidly signalled to other communities along the coast.
The Republic of Genoa also had to deal with many financial conflicts, quarrels of communities, defection of guards, unpaid debts, and requests for supplies or weapons.
When Pasquale Paoli was elected President of the new independent Corsican Republic in 1755, only 22 towers remained, some of which were occupied by the French troops.
The continual guerrilla wars during the paolian period caused the destruction of several of these buildings, including the towers of Tizzano, Caldane, Solenzara.
The battle for the landing of the British troops of the Anglo-Corsican Kingdom in 1794 ruined the towers of Santa Maria della Chiappella and Mortella.
The garrison of a tower consisted of between two and six men (Corsican: torregiani), recruited among the inhabitants and paid from the local taxes.
In the event of alarm, a signal was given on the terrace at the top of the tower, in the form of smoke, fire or the sound of culombu (a large conch), warning the surroundings of the approach of hostile ships.
The vaulted room on the first floor was connected to the terrace by a staircase built into the thick exterior wall and protected at the top by a small guerite.