War II. His cult was confirmed on August 26, 1727, by Pope Benedict XIII. He is also venerated in the Eastern Orthodox Church, his feast day being October 22. References External links Saints.SQPN: Bertharius Catholic Online: Bertharius Abbots of Monte Cassino 810s births 883 deaths 9th-century Christian martyrs Christian saints killed by Muslims Italian Roman Catholic saints Canonizations by Pope Benedict XIII