It is likely that existing contacts of Gentileschi, such as the Viceroy of Naples (Manuel de Acevedo y Zuniga), helped secure the commission for her.

He was made Bishop of Naples (where he is still the patron saint) and his protection of Christians raised the ire of the Roman Emperor Diocletian.

Diocletian expected him to be attacked by the wild animals, but Gentileschi illustrates the moment that the lion and bear are tamed, and with great docility show their obedience to the Bishop.

[4] Along with Saints Proculus and Nicea and Adoration of the Magi, the painting of Januarius was commissioned from her for the choir of Pozzuoli Cathedral.

Others have pointed to the need to use a particular tone that would blend with the other paintings created for the renovation of the cathedral - this would have obliged Gentileschi to work in a slightly more muted style.