One of the images we first think of when we think of a Rosary Shrine is the famous from the Shrine of Our Lady of Pompeii, depicting Our Lord and Our Lady giving the Rosary to Saint Dominic and Saint Catherine of Siena.  The addition of Saint Catherine here makes the image ahistorical, more than merely allegorical, since Saint Catherine of Siena herself would be born more than 125 years after the death of Saint Dominic.   But such pious mismatch of saints in historical time is hardly unique --  you might well find St. Peter the Apostle alongside St. Francis of Assisi in some classical piece of art, for example.  For Our Lady of Pompeii, this particular artist or the person who commissioned the piece was devotionally attached to both Our Lady of the Rosary and Saint Catherine of Siena, perhaps the most famous and imposing woman saint of the Dominican Order of her glorious history, and likewise well-known and beloved in her native Italy.

But of this particular image's origin we know very little.  Fr. Johann Roten, S.M. writes in an article elsewhere (found online at the University of Dayton):

The original was bought by Fr. Alberto Radente, OP, for 3.40 lira in a pawnshop in Venice. He gave it to a tertiary in Naples who in turn gave it to Blessed Bartolo Longo (1841-1926), a devout layman and founder of the sanctuary of Pompeii. It was in pitiful condition and needed restoration. After completion of the restoration, it was considered of "heavenly beauty." The painter is not known. 1

It is incredible to think that such a beautiful and beloved image was barely noticed in a pawnshop, discarded, gathering dust.  But, with loving attention, this "worthless" image was restored to perhaps even greater glory than it had when it was painted.  But such is the life of the soul of Bl. Bartolo Longo as well, who had fallen into Satanism, but was rescued from the pit of eternal death with the aid of Our Lady of the Rosary, transformed from a child of darkness into a child of God's own wonderful light.  It is likewise a sign that the Rosary, though entrusted to Saint Dominic, a priest, is likewise entrusted to all who love Our Lady and her Rosary through Saint Catherine of Siena.

Likewise, my brothers and sisters, regardless of what worth the world assigns you, know that you are more precious than the finest piece of art in all the world, always ready to be restored to greater glory with a little tender love and care from Our Lord, should you too fall into a little spiritual disrepair.

O Saint Catherine of Siena, pray for us!