Gioacchino Martorana, son of the painter Pietro Martorana and pupil of Marco Benefial in Rome, is an exponent of 18th-century classicist and rococo painting. Born in Palermo in 1735 and very active in Rome with important commissions, he returned to Sicily and worked on several projects for the Monreale Cathedral, all characterised by a detailed study of light and attention to design. The artist painted a documented cycle of frescoes in the refectory of the Seminary in the Archbishop’s Palace. They feature the Triumph of Religion and William’s Dream, as well as two altarpieces with Our Lady Appearing in a Dream to William II and Our Lady between Saints Peter, Charles Borromeo and Philip Neri for the Archbishop’s Seminary. The ‘William’s Dream’ painting, dated between 1768 and 1769, composed on diagonal lines is a dynamic altarpiece, with bright and vivid colours. At the top, surrounded by putti and angels and supported by clouds, is the Virgin, wrapped in a blue mantle. The sovereign rests on a rock, blissful in his dream, with his crown lying gently at his side. The narrative of the Dream is striking, made even more exciting by the spatial placement of numerous symbols: a bow, arrows and two cherubs playing while collecting treasure coins.