View of the apse calotte

Pope Nicholas IV commissioned the mosaic decoration of the apse of Santa Maria Maggiore, replacing the fifth-century mosaic but without entirely changing the original subject matter and retaining the bust of the Saviour, believed to have appeared miraculously at the time of the basilica’s consecration. The task was given to Jacopo Torriti, who left the Lateran workshop around 1291 to assist the work at Santa Maria Maggiore.