Read this: The Monreale mosaics constitute the largest decoration of this kind in Italy, covering 0,75 hectares with at least 100 million glass and stone tesserae. This huge work was executed between 1176 and 1186 by the order of King William II of Sicily. The iconography of the mosaics in the presbytery is similar to Cefalu while the pictures in the nave are almost the same as the narrative scenes in the Cappella Palatina. The Martorana mosaic of Roger II blessed by Christ was repeated with the figure of King William II instead of his predecessor. Another panel shows the king offering the model of the cathedral to the Theotokos.
Now answer this question, if there is an answer (If it cannot be answered, return "unanswerable"): Who commissioned the Monreale mosaics between 1176 and 1186?
King William II of Sicily