The Burial of Saint Petronilla

Petronilla was venerated in Rome as the daughter of Saint Peter. The legend says she refused to marry a pagan nobleman called Flaccus and died after days of fasting and prayer. Her relics had been kept since the 8th century in a chapel beside the old basilica, a chapel the kings of France regarded as their own, and in 1606 they were moved into the new Saint Peter's. On 28 December 1621 Pope Gregory XV ordered a painting for her altar there from Guercino, who delivered it in 1623. It is more than seven metres tall and tells the story on two levels. Below, men lower her body into the grave in a warm light. Above, she bows before Christ, who welcomes her while a small angel brings the crown of martyrdom. In the 18th century the altarpieces of Saint Peter's were replaced one by one with mosaic copies, and in 1730 a copy by Pietro Paolo Cristofari took this one's place, where it still stands. The canvas went to the papal palace on the Quirinal, was carried to Paris by Napoleon's troops, came back with the sculptor Antonio Canova and was hung here in 1818, in the room that now bears the saint's name.