Monaco Ville was originally called in Greek Monoikos, after the temple of Hercules Monoikos, located in a Phocaean colony of the 6th century BCE. During its history, Monoikos changed hands numerous times. It became Monaco in the Middle Ages. Some of the city walls and original structures still remain.

It was here that the Phocaeans of Massalia (now Marseille) founded the colony of Monoïkos in the 6th century BC. Monoikos was associated with Hercules, who was worshipped as Hercules Monoecus. According to the works of Hercules, but also according to Diodorus of Sicily and Strabo, the Greeks and the Ligurians reported that Hercules had passed through the region.

On 10 June 1215, a detachment of Ghibellines led by Fulco del Cassello began the construction of a fortress on the rock of Monaco in order to make it a strategic military position and a means of controlling the area.

They also established dwellings at the base of the Rock to support the garrisons. To attract the inhabitants of Genoa and the surrounding towns, they offered land and exempted newcomers from taxes.

On January 8, 1297, François Grimaldi, descendant of Otto Canella, consul of Genoa in 1133, took over the fortress. Although he had a small army, he disguised himself as a Franciscan friar to enter, before opening the gates to his soldiers. This episode gave rise to his nickname, Malizia ("malice"). This is why today the arms of Monaco bear two Franciscans armed with a sword.