Leaf from a Gradual: Initial M with Saint Andrew (1480) by Jacopo Filippo d' Argenta - Public Domain Catholic Painting

This leaf was excised from a volume of a large set of choral books known to have been commissioned by Bartolomeo delle Rovere for Ferrara Cathedral. Delle Rovere, nephew of Pope Sixtus IV, was the Bishop of Ferrara from 1474 to 1494 and his arms appear in the rondel at the bottom of the page-a shield bearing an oak tree (rovere in Italian) surmounted by a patriarchal cross, the symbol of his rank and authority.

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