The Bishop of Caithness was the ecclesiastical head of the Diocese of Caithness, one of Scotland's 13 medieval bishoprics. The first referenced bishop of Caithness was Aindréas, a Gael who appears in sources between 1146 and 1151 as bishop. Aindréas spent much if not all of his career outside his see.
Other bishops before Aindréas are possible, but none is documented. King David I of Scotland, is credited with founding many bishoprics, and it is possible that Caithness was one of them. Little documented history exists before the reign of King David.
The earliest bishops resided at Halkirk, with a castle at Scrabster. Bishop Gilbert de Moravia moved the episcopal seat to Dornoch in what is now Sutherland (then regarded as part of Caithness), and the bishopric remained at Dornoch Cathedral for the remainder of its existence. The Bishopric of Caithness' links with Rome ceased to exist after the Scottish Reformation, but the bishopric continued, saving temporary abolition between 1638 and 1661, under the episcopal Church of Scotland until the Revolution of 1688 led to the permanent abolition of episcopacy in the established church in Scotland (now Presbyterian in government) in 1689.