On 29 August 1512, during the years of clashes between Pope Julius II and the French crown (the latter supported by Venice and the Italian princes), the city of Prato was besieged by the Spanish troops of the Viceroy, Raimondo de Cardona.
The Spanish entered the city and laid waste to it in a succession of dramatic events, murders and rapes.
The attack on Prato, however, was no more than a pretext for conquering the nearby Florence.
The aim was that of restoring the old glory of the Medici family, which in those years had been driven from Florence in order to establish a Republic. The sack of Prato, in which so many of its citizens lost their lives, induced Florence to bring back the victorious Medici, who regained possession of the city.
A miraculous event that took place in the midst of this devastation has endured and become a famous part of Prato's historical memory. Legend has it that three Spanish captains entered the female convent of San Vincenzo to plunder it, but converted and abandoned their plan because of the intervention of the Virgin Mary, who appeared to them in a terracotta sculpture. Since then, the statue has been called Madonna dei Papalini and the extraordinary event is still being commemorated every year on 29 August.