THE MYTH
In Roman mythology, the Genius (from the Latin gignere – to give birth to) is the deity who presides over the birth of an individual and accompanies him throughout his life. The Genius of the Emperor was a common focus of worship across the Empire. By extension, anything that has an evolving identity has a Genius, such as a place, building, community, or city. The Genius of the city is the spirit that protects the city over time, and guarantees its welfare and prosperity.
THE ICONOGRAPHY
The typical form of the Genius of a city is a male figure wearing a toga or cloak. Sometimes he wears a crown, reminiscent of the walls of a city, and holds a cornucopia, symbol of prosperity, or patera (offering bowl), as illustrated in frescoes from Herculaneum. He can also be represented as seated on a rock, with a mantle wrapped around the legs, or else depicted in the form of a snake, as a bearer and giver of life.