William II of Sicily, known as "the Good," reigned from 1166 to 1189, distinguished by the stability and pacification of his government. He was a patron of the arts, supporting the construction of the Monreale Cathedral, the Abbey of Santa Maria di Maniace, and the completion of the Zisa. His religious tolerance allowed Muslims prestigious roles and freedom of worship. His reign, marked by peaceful coexistence among diverse populations, left a lasting imprint on Sicilian art and culture. His death in 1189, without heirs, paved the way for significant dynastic changes.