The St. Magnus Cathedral is the cathedral of the city Kirkwall on Orkney in Scotland. The cathedral is dedicated to St. Magnus. It houses the mortal remains of the saint. The cathedral is known as "The Light of the North". In 1137, the St. Magnus Cathedral was founded by Count Rognvald-Kali. He was a nephew of St. Magnus. Before the Reformation, the cathedral belonged to the Archdiocese of Trondheim. In 1468 Orkney came to the Scottish kingdom. In 1486 the cathedral was handed over to the inhabitants of Kirkwall.
In the wake of the Reformation in Scotland, worship at the cathedral was reformed in 1560. But there was no iconoclasm, unlike many churches on the Scottish mainland. From then until 1688, St. Magnus Cathedral was the episcopal church of the Church of Scotland. After the episcopal-minded bishop had left office in 1688, the cathedral became a Presbyterian church. Today the cathedral is used by the Church of Scotland.
Renovations took place in the 1850s and between 1900 and 1925. In these years, a new floor, the windows and the crossing tower have been added. In the 1970s, the cathedral was stabilized as it had sunk slightly to the west.