Ecclesius was a 6th-century bishop who led the see of Ravenna from 521 until his death in 532. He is most recognized for initiating the construction of the Basilica of San Vitale, a project he undertook with the financial assistance of Julian the Banker. During his tenure, he navigated complex political and religious tensions, including a mission to Constantinople alongside Pope John I to oppose imperial edicts regarding Arianism. Despite facing local clerical opposition, his leadership was formally upheld by Pope Felix IV.