Innocent III was a significant pope for the mediaeval church. He approved the first Rule of St Francis, a key spiritual occurrence of the times and also became the protagonist of an episode in the Legenda maior, St Francis’ biography written by Bonaventura da Bagnoregio. Innocent III was the guardian of the future Emperor Frederick II and his political actions sought to strengthen the spiritual and temporal power of the Church – something that – as occurred throughout the Middle Ages – had a major impact on artistic production. Innocent III decided to renew the apse mosaic of St Peter’s Basilica in the Vatican, the iconography of which centred on the concept of the supremacy and power of the Church of Rome, directly descended from Jesus Christ. This renewal project included the execution of decorations in the interior of the Basilica, of which the Lunette formed part.