The paper looks at the issue of the seat of Methodius's Pannonian Archdiocese. In the opinion of a number of scientists, the seat of the archdiocese was located in the city of Sirmium, i.e. modern day Sremska Mitrovica. Based on rather scarce narrative, diplomatic, and archaeological sources, the author concludes that the seat of the archdiocese could not have been in Sremska Mitrovica. The paper presents the conclusion that any church organisation that was likely to have existed in the territory of Srem, now and then, was more likely to have been in connection to the church organisation of the Bulgarian state than it would represent a remnant of the abandoned Methodius's Pannonian Archdiocese.
