The Abbot of Monte Cassino, Desiderius sent envoys to Constantinople some time after 1066 to hire expert Byzantine mosaicists for the decoration of the rebuilt abbey church. According to chronicler Leo of Ostia the Greek artists decorated the apse, the arch and the vestibule of the basilica. Their work was admired by contemporaries but was totally destroyed in later centuries except two fragments depicting greyhounds (now in the Monte Cassino Museum). "The abbot in his wisdom decided that great number of young monks in the monastery should be thoroughly initiated in these arts" – says the chronicler about the role of the Greeks in the revival of mosaic art in medieval Italy.

Who hired Byzantine experts to decorate a rebuilt abbey church?