Viator of Bergamo was a 4th-century bishop who served as the second leader of the see in Bergamo. Following the leadership of Saint Narnus, he held his position as bishop from approximately 343 until his death in 370. During his career, he participated in the Council of Sardica to address theological disputes regarding Arianism. His contributions were significant enough that Saint Athanasius identified him as a co-author of the decree *Apologia contra Arianus*.