The early Norsemen in Orkney built their houses of wood imported from Norway, with only a slight foundation of stone; and the Norse theory of defence lay in attacking the foe, preferably on sea. Save, therefore, for a few buildings erected by Jarl or Bishop, and by one or two powerful Viking chiefs, stone masonry during the purely Norse period (870-1231) was practically confined to churches. Even during the Scoto-Norse (1231-1468) and Scottish periods men of sufficient power and wealth to erect imposing buildings of stone were still few. Compared, therefore, with an ordinary Scottish county the castellated architecture of the Islands is meagre in quantity; but several of the buildings of this class that remain are of exceptional interest and beauty.

At the north end of the island of Westray stands Noltland Castle, the only ancient military structure which Orkney can now show in a state of comparative preservation. The castle is clearly of two periods, but the best authorities now reject the once prevalent idea that the earlier portion could have been erected by Thomas de Tulloch, Bishop of Orkney from 1418 to 1460. The building is supposed to have been added to and beautified by a later Bishop, Edward Stewart, yet so late as 1529 Jo Ben described it as “Arx excellentissima sed nondum completa.” Adam Bothwell, the first protestant Bishop, feued the castle to Sir Gilbert Balfour, Master of the Household to Queen Mary, and a doubtful tradition says that Balfour had orders to prepare the place as a retreat for the Queen and Bothwell. Finally the place gave refuge to some officers flying from Montrose’s defeat at Carbisdale, and was on that account fired and left dismantled by Cromwell’s soldiers. The great staircase of Noltland is one of the finest in Scotland, excelled only by those of Fyvie and Glamis Castles. Another special feature of the castle is the exceptional number of shot-holes, splayed both outwards and inwards, which give its exterior walls the appearance of the hull of an old style man-of-war.

The Earl’s Palace at Kirkwall, built by Patrick Stewart, Earl of Orkney, about 1600, is one of the most beautiful specimens of domestic architecture in Scotland, and more regal in appearance than anything north of Stirling and Linlithgow. Fronting west, the building forms three sides of a square, and is practically entire save for the roof. On the ground floor is the grand hall, a magnificent apartment about 55 feet long by 20 feet wide, lighted by three splendid oriels, and a triple window in the gable, divided and subdivided by mullions and transoms. There are two fireplaces in the room, one being 18 feet wide. At the landing of the main stair there is a beautifully arched apartment of about 9 feet long by 7½ feet wide, commonly styled the chapel, but which may have been a waiting room. “It is a superb specimen of Scottish seventeenth-century architecture, its oriel windows and turrets being unsurpassed by anything on the mainland, and it is so rich in its details, and spacious in its accommodation, that it is with more than usual regret that one looks on its roofless and decaying walls.” The palace has not been inhabited since towards the close of the seventeenth century.

The Bishop’s Palace at Kirkwall, which stands in close proximity to the Earl’s Palace and the cathedral, is supposed to have been erected by Bishop Reid (1540-1558), on the site of an earlier building, in which King Hakon Hakonson died in 1263. A prominent feature of this building is its great length, originally about 196 feet, from which it is supposed that it formed, or was intended to form, one side of a quadrangle. Above what was originally the main entrance is the corbelling of a fine ruined oriel. There is a five-storeyed round tower at the north-west corner of the building, which contains in a niche of its exterior wall a statuette long erroneously believed to represent Bishop Reid. The chief apartment of the palace appears to have been about 26½ feet long by 24 feet wide. Part of the structure is still occupied.

Overlooking the sea, in the extreme north-west of the Mainland, stand the ruins of the Palace of Birsay, erected by Robert Stewart, Earl of Orkney, about 1580, on the site of an old palace of the Norse Jarls. Less elaborate in design, and in a worse state of preservation than the building erected by his son, Earl Robert’s palace is sufficiently commodious and noble of outline to make one marvel at the passionate taste for fine buildings of a race which required two such imposing structures in two successive generations. Earl Patrick is said to have partly reconstructed his father’s building, modelling his alterations on Holyrood, but the building as it stands more resembles the later courtyard at Dunottar Castle.