One of the more unusual features in Botticelli’s Primavera is the figure of Mars shown facing out of the frame. Art historian Barbara Deimling suggests the figure represents Mercury and “its direction of movement leads not into an empty space but on to the painting of Pallas and the Centaur, which originally hung to the left of Primavera, over a door”.

In his monograph on Botticelli the late Ronald Lightbown also nominates the figure as Mercury and suggests it is his steel cap that gives “the clue to his role in the garden about which there has been so much confusion”, and that “he wears a winged helmet because he is the guard who keeps entrance to the garden”, and “why the harpe [sword] is so prominent and why he wears a military cloak, why he stands with his back to the other figures expelling the intrusive clouds with his caduceus…”

Botticelli also presents the figure as Mars, superstitiously viewed in earlier times by the Florentine people as a protector of the city. According to the chronicler Giovanni Villani, a statue of Mars on horseback stood on a pedestal at the Ponte Vecchio, looking East. In 1300, it was temporarily moved while repairs were carried out on the old bridge. However, when the statue was returned to the bridge it was placed facing North. This did not go down well the people and Villani records their words: “May it please God that there come not great changes therefrom to our city”.

Thirty-three years later Mars was unable to protect Florence from disaster when the Arno river flooded and the rising waters overwhelmed the city defences. Even the statue of Mars was swept away in the flood, never to be seen again. Villani describes the event: “And when Mars had fallen and all the houses between the Ponte Vecchio and the Carraia bridge had come down and all the streets on both banks were covered with ruins, to look at the scene was to stare at chaos.”

No attempt was made to replace the pagan statue. Instead, the Florentines focused on a new symbol of protection and status – that of a lion – the Marzocco. 

So Botticelli’s figure of Mars attempting to sweep away the rain clouds can be viewed as a pointer to the time of the Great Flood of 1433 and the earlier time the statue was turned from facing East to North. 

However, there was another unfortunate event associated with the statue of Mars at the Vecchio bridge – the murder of a young nobleman named Buondelmonte de’ Buondelmonti, killed on Easter Sunday in 1215. This links to Botticelli’s figure of Mars when identified as Giuliano de’ Medici who was assassinated while attending Mass in Florence Cathedral on Easter Sunday, 1478.

Botticelli sourced the Buondelmonte narrative to form the basis of Primavera’s composition and the painting’s principal theme of reconciliation and peace associated with the city of Florence.

Botticelli’s pairing of Giuliano de’ Medici with the statue of Mars, an assassination and a drowning, could be see later as somewhat prophetic, when Giuliano’s nephew, Piero di Lorenzo de’ Medici (Piero the Unfortunate), died by drowning as he crossed the Garigliano River while attempting to flee from the aftermath of the Battle of Garigliano in 1503.

The Renaissance artist Andrea Mantegna portrayed Piero as Mars in his painting Parnassus (1497), a parody of Primavera and a tribute to Botticelli. The image on Piero’s breastplate is that of Botticelli, suggesting that Mantegna was fully aware of the disguised narratives Botticelli had embedded in Primavera.