Back in the late 16th century, Pope Gregory XIII became pretty much obsessed with mosaics. He brought Venetian mosaic artists to Vatican City specifically to teach their trade to Roman craftsmen, who soon set about decorating parts of St. Peter’s Basilica, including the Gregorian Chapel and the Dome of Michelangelo.
Such was the success of this new artistic initiative that mosaics spread to other cupolas in the Basilica, becoming an integral part of this masterpiece of Renaissance architecture.
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