In 1519, a year before his death, Raphael completed the painting of a long, narrow gallery in the Vatican Palace. In this gallery with a long open arcade, the brilliant artist produced together with his pupils what went down in history as "Raphael's Bible". Fifty-two frescoes on biblical and mythological subjects adorned the thirteen domes of the loggias in the Vatican, testifying to the inexhaustible artistic imagination of their creator.

On 1 September 1778 Empress Catherine II viewed Volpato's engravings of the frescoes in the Vatican gallery and was so enchanted with them that she made "an oath to St Raphael whatever the cost to construct those loggias and to install copies in them." She wrote of her decision to Melchior Grimm: "I have such reverence for those loggias and ceilings that in their honour I am sacrificing funds for the construction of a building and shall have neither peace nor rest until everything is completed."