The Bishop of Dunkeld is the ecclesiastical head of the Diocese of Dunkeld, one of the largest and more important of Scotland's 13 medieval bishoprics, whose first recorded bishop is an early 12th-century cleric named Cormac. However, the first known abbot dates to the 10th century, and it is often assumed that in Scotland in the period before the 12th century, the roles of both bishop and abbot were one and the same. The Bishopric of Dunkeld ceased to exist as a Roman Catholic institution after the Scottish Reformation, but continued as a royal institution into the 17th century. The diocese was restored (with a different boundary) by Pope Leo XIII on 4 March 1878; it is now based in the city of Dundee.
Dunkeld abbey was an offshoot of Iona, perhaps founded in the early 9th century, in the reign of Caustantín mac Fergusa, King of the Picts. It is not clear when its abbots got independence from the Abbots of Iona, but a notable event is the alleged transfer of the relics Columba to Dunkeld during the reign of the Scoto-Pictish king Cináed mac Ailpín. Its abbots, like many Gaelic abbots of the period, took a strong role in secular affairs, hence the term "lay abbot". The following is a list of known abbots of Dunkeld; the list is not exhaustive.
The Annals of Ulster, s.a. 865.6, records his obit and writes "Tuathal m. Artgusso prim-epscop Fortrenn & abbas Duin Caillenn", that is, "Túathal son of Artgus, chief bishop of Fortriu and Abbot of Dunkeld [dies]".
The Annals of Ulster, s.a. 873.8, records his obit and writes "Flaithbertach m. Muirchertaigh, princeps Duin Chaillden, obiit", that is, "Flaithbertach son of Muirchertach, superior of Dún Caillen, died".
While it is true that medieval churchmen took an active part in secular affairs (some fought in battles), that didn't make them in any sense "lay." They were still consecrated bishops or abbotts. A "lay abbott" was the secular lord of the abbey's lands. Since an abbey's property was often extensive, it was lucrative plum. Medieval monarchs enjoyed considerable authority over the church, and doubtless these positions were awarded to royal favorites.
Anti-Bishop of the Western Schism. Consecrated by Peter, Bishop of Citta Nuova, in October 1379 on order of Pope Urban VI, in opposition to John de Peblys, supporter of the Avignon Pope. Never took possession of see.
English abbot (of Pershore); was the nomination of the Pope against the candidate of the Avignon Pope during the Western Schism. Never took possession of see.
(Any dates appearing in italics indicate de facto continuation of office. The start date of tenure below is the date of appointment or succession. Where known, the date of installation and ordination as bishop are listed in the notes together with the post held prior to appointment.)