Until the 10th century, the diocese itself appears in none of the Notitiae Episcopatuum. By 980, they present it as an autocephalous archdiocese, and those of the 11th century present it as a metropolitan see with 21 suffragans. This was the time of greatest splendour of Acilisene, which ended with the decisive defeat of the Byzantines by the Seljuq Turks at the Battle of Manzikert in 1071 when the Seljuqs invaded.[6] The diocese survived the Islamic invasion and was still extant when Marco Polo visited the town. After the 13th century there is no mention of diocesan bishops of Acilisene and the see no longer appears in Notitiae Episcopatuum.[7]