In the twilight years of the Roman Empire a soldier named Sebastian serves in the Praetorian Guard under the Emperor Diocletian; the Empire is declining and Diocletian is looking to restore it to glory.

In the early 13th century, Francis, once wealthy and frivolous, is transformed by a profound spiritual awakening and a commitment to poverty and service. This transformation is often linked to his experience in war, his time as a prisoner, and a powerful encounter with a crucifix, leading him to renounce his privileged life and embrace a life of simplicity and dedication to the teachings of Jesus.