The Illyricum orientale after the Sixth Century

Abstract This article deals with the history of the so-called Illyricum orientale after Justinian. Due to the Slavic immigration in the Balkans and especially Greece, the importance of the bishoprics of the Eastern Illyricum diminished, even if their subordination to Rome and the vicariate of Thessalonikē had not been forgotten in the seventh century. During the Sixth Ecumenical Council (680/681), Basileios of Gortyn (Crete) played a role as representative of the papacy. In the subscription list, the bishoprics of Eastern Illyria were listed separately. This changed in 692 during the so-called Quinisextum , when these bishoprics were categorized under those of the Patriarchate of Constantinople. It can therefore be assumed that this change finally happened between 681 and 692 – and not under Leon III in the eighth century.