Scotland's deeply troubled and turbulent history has left a remarkable legacy in the form of large numbers of castles dotted across the landscape. These range from sites barely visible on the ground through every stage of ruin to magnificent buildings that over centuries of development evolved into something much closer to a palace than a mere castle. The exact number is unknown, but if you include only the range of buildings from the last millennium discussed on this page, there could be two thousand or more castles in Scotland.
People have been finding ways of defending themselves, their families and their belongings for thousands of years, resulting in large numbers of hillforts, brochs, duns and crannogs, not to mention the various defensive sites built by the Romans during their excursions into Scotland.
The centuries between the final departure of a Roman presence in northern Britain and the arrival of King David I on the throne in April 1124 saw recurrent conflict across many parts of the area we now call Scotland among and between the Scots, Picts, Britons, Angles and Norse. It is inconceivable that the participants ignored the defensive possibilities of fortifications left by their ancestors, or that they failed to build fortifications to defend their own settlements: but we'd probably stop short of describing what emerged as "castles".
It was David I's extensive "Normanisation" of Scotland in the middle of the 1100s that first saw widespread castle building here. The castles erected in the 1100s were of various types. The new class of immigrant Norman nobles, and the resident Scottish lords who sought to emulate them, were quick to build structures to defend their newly granted lands and estates across Scotland. In areas where the likelihood of armed opposition was high, such as Galloway, Clydesdale, Moray and Aberdeenshire, the favoured approach was to construct a motte, an artificial mound of earth in the shape of an upturned pudding bowl, topped by a defensive structure often in the form of a wooden tower. It was also common for natural outcrops to be enhanced and fortified, as at Mote of Urr in Dumfries & Galloway. Many mottes were accompanied by baileys, often larger "courtyards" raised above the surrounding area to a lesser degree, or not at all, defended by a wooden palisade and containing domestic buildings. The motte, or the motte and bailey together, would usually be surrounded by a defensive ditch or moat. A good surviving example is Duffus Castle.
In the less troubled central areas of Scotland, where the nobles still wanted to feel secure but didn't need to put so much effort into it, the standard approach was to construct a ringwork, a defensive wall or palisade on top of a bank, plus a ditch, thrown round a farmstead or hall. These were probably more common than mottes, though fewer traces of them have survived. This was also the century in which a series of royal castles appeared across Scotland, bases from which the King could govern the country. Some of these were in the form of mottes, but others were more ambitious stone tower-keeps, for example at Edinburgh Castle (the only fragment remaining of this is St Margaret's Chapel), Carlisle Castle and the first stage of Aberdour Castle.
Rather surprisingly, the most advanced castles being built in Scotland at the end of the 1100s were not within the area of control of the Scottish Kings at all, but were built on the western and northern margins occupied by the Norse or the Norse/Celtic descendants of Somerled. Cubbie Roo's castle on the Orcadian island of Wyre and the Castle of Old Wick both took the form of stone tower quite like the tower houses that would be built across Scotland several centuries later.
The 1200s are sometimes called the "golden age" of castle building in Scotland. Many minor castles built during the century adopted the motte or the ringwork patterns already well established, but the main interest lies in the exceptions to this, amongst which are some of the earliest and most impressive of the castles that still survive today. These were the curtain-walled castles that started to appear from about 1200, whose outward appearance was of a massive defensive, often almost featureless, wall, within which would have been stone or wooden buildings.
The first examples of this style occur in the Norse-influenced margins of the country, at places like Castle Sween, Castle Tioram and Rothesay Castle. Perhaps because the Norse were able to breach the walls at Rothesay Castlein 1230, major castles built later in the century tended to incorporate circular towers that projected beyond the walls and could help protect them from attack. Examples include Kildrummy, Bothwell, Dirleton and Inverlochy Castles, while some existing curtain wall castles like Rothesay and Dunstaffnage had circular towers added to the existing structure to strengthen their defences.
Almost lost in this story is a further type of castle: the hall castle. At places like Aros on Mull, Skipness in Argyll, and Rait Castle south of Nairn, a stone hall and other buildings were initially surrounded by defences constructed of earth and timber. Where these existed, they had usually been converted into curtain wall castles by about 1300, so few signs of them remain: the most important survivor is Rait Castle.
The 1300s saw the castles of the previous century put to the test, often repeatedly, during the Wars of Independence between Scotland and England which started in 1296. Most Scottish castles proved easy prey to attackers, whether in Scottish or English hands at the time. Some castles such as Stirling were repeatedly captured and re-captured over the first few decades of the century. Even the supposedly impregnable Bothwell Castle proved incapable of withstanding a really determined and well-equipped attack. The most outstanding exception to this was the successful defence of Dunbar Castle under the command of Agnes Randolph, Countess of Dunbar, against everything that the well-equipped English could throw at it.
It is tempting to think of this as an indication of failure on the part of the castle builders of the previous century. But you need to remember that relations between Scotland and England were cordial until 1296, and that as a result most Scottish castles were designed primarily for prestige, or, at worst, to defend against the enthusiastic but often transient threat of the sea-borne Norse. They were certainly never designed to withstand a large English army complete with siege engines turning up at the front gate, so the failure of most of them is perhaps not too surprising.
During the century, efforts to ensure that castles could withstand this new set of threats led to a boom in castle building (and in the alteration of earlier castles). The English added a massive gatehouse to Kildrummy Castle that seems to have been built by the same man who had just built Harlech Castle for them. Castles built from scratch by the English at places like Lochmaben, Linlithgow and Selkirk, often called "peels", were erected quickly, and mostly of earth and wood. As a result few signs of them have survived and most were later replaced by more permanent structures. Meanwhile castles continued to be built that were virtually indistinguishable from the mottes of the previous two centuries, presumably because in time of real danger, they were far quicker to construct than a stone castle: and probably no more vulnerable to determined attack.
The relatively peaceful second half of the 1300s saw the construction of Scotland's last great curtain walled castle, at Tantallon, but this was a unique project in a country that was starting to turn with enthusiasm to stone tower-house castles. In many cases these simply replaced timber defensive structures built in earlier centuries. Where they survive, castles like Threave and Hallforest give the impression of isolated and self-contained towers. In fact the tower-house castles built during this period usually comprised a stone tower and a relatively modest surrounding wall also containing ranges of other buildings which have often not survived. An example of a tower-house castle from this period that has survived as originally built is Doune Castle.
The 1400s saw a new challenge to castles emerge in the form of the gun. Artillery trains suddenly became an essential part of an army, and castles like Roxburgh, in long-term English occupation, began to bear the brunt of successive Scottish Kings' enthusiasm for this new form of warfare.
But despite this, the 1400s were actually a relatively peaceful time in Scotland, certainly when compared to the previous century, and this gave the stability needed for investment in long term projects like stone castles. At the same time, the Crown's challenge to the power of the great Barons resulted in a much larger class of lesser landholding lairds, all of whom wanted to mark their arrival on the social scene, and the landscape. The result was a boom in castle building.
Many of the new castles erected during this period were tall tower houses such as Cardoness Castle, Crichton Castle, Orchardton Tower, Smailholm Tower and the largest of them all, Borthwick Castle. Like earlier tower houses these would have been accompanied by ancillary buildings, usually including a hall and kitchen, and surrounded by a defensive wall. Meanwhile, earlier castles damaged in the previous century were often remodelled by the insertion of a tower house: with good examples at Dirleton Castle and Bothwell Castle. Another trend during the century was the increasing use of highly elaborate wall-head defenses, which it's tempting to suggest were at least as much for show as for real defence. This was perhaps the first deliberate step away from defence and towards display and prestige, a trend that was to provide one of the two main strands of the castle's development over the following centuries.
The second strand was to see castle builders trying to find innovative and effective ways of protecting a small number of truly defensive castles against the worst that could be thrown at them - literally - with the advent of the gun. The first real example of this was at Threave Castle, where the Black Douglas family were forced to defend themselves against the Scottish Crown. At Threave the family cleared away many of the buildings on the island to improve the lines of fire for three gun towers built in front of the existing castle. These were designed specifically to allow attacking artillery to itself be attacked. Meanwhile, Craigmillar Castle near Edinburgh was also adapted to allow the defenders to use artillery, and Ravenscraig Castle in Fife was built with a massive foretower designed both to absorb an artillery attack and allow the defenders to retaliate.
The tendency to build massive stone structures to try to withstand and repel artillery carried on into the 1500s. A huge blockhouse built at Dunbar Castle was one example, as was the new artillery tower built at the landward end of Blackness Castle. Both had stone walls up to 20ft thick and were provided with gunloops to allow artillery to fire from within them, and broad ramparts to allow guns to be fired from the top of the walls. Elsewhere castles like St Andrews and Tantallon were also strengthened. Perhaps the ultimate expression of this trend was Craignethan Castle in Lanarkshire, built in 1532. In many ways this resembles a normal tower house of the time and stands on a spur projecting above the valley of a tributary of the Clyde. But when originally built the side facing away from the protection of the valley was defended by an awesome structure, a huge stone wall, 16ft thick and with ramparts that would allow artillery to be mounted on top.
On the continent, stone defences against artillery had by this time already been overtaken by bastions comprising angled banks of earth fronted by ditches, intended to absorb the fire of artillery without damage to the structure. It seems that the eastern end of Edinburgh Castle was defended in this way in the 1540s, and the English built entire fortifications along these lines after their invasion of 1547. Traces of their fortifications at Eyemouth can still be seen on the ground, but their largest fort, at Haddington, has long since disappeared. This sort of defensive works became known as trace italienne.
Despite these developments, most castles built in Scotland in the 1500s, were variants on the earlier theme of tower houses. In many cases they were larger than those of the previous centuries, and designed to remove the need for a separate hall and kitchen by incorporating them within the tower itself. Many were also equipped with gun loops to allow defenders to make the most of the new technology. But as defensive structures these tower houses were simply not intended to keep out armies equipped with artillery: if they kept the occupants safe from cattle-raiders or the occasional angry neighbour, they were doing what they were designed for.
These tower houses came in a bewildering array of shapes and sizes, including rectangular, L-shaped, E-shaped (with and without the central stem of the E), Z-shaped, and T-shaped, and their main role was to provide all-in-one accommodation for the laird, his family and retainers. Meanwhile, at the upper end of the social scale, castles, having been overtaken by bastions as state-of-the-art defensive structures, instead expressed the status of their occupants by becoming opulent palaces, as at Huntly Castle, Linlithgow Palace and Falkland Palace.
Although the Scottish nobility actively continued to build castles until a much later date than their English counterparts, the story of the development of the castle really doesn't extend very far into the 1600s. Although Scotland was a deeply troubled place for much of the century, defence was increasingly seen as less important than comfort and prestige, and the 1600s saw the mass migration of castle-dwelling lairds into much more comfortable manor houses. Sometimes these were built near the castles that preceded them, sometimes they were built onto the side of them, and sometimes they simply incorporated the earlier structures.
When Cromwell invaded Scotland in 1650 he did so with overwhelming force and a large train of artillery. Whenever anyone tried to stand in his way or harry his troops, his response was uncompromising, simply destroying any bases of operation his opponents might be using. The list of castles built in earlier centuries across Scotland whose obituaries read "destroyed byCromwell" or, at least, "rendered unusable by Cromwell" is extremely long. Having conquered and annexed Scotland, Cromwell controlled it from a series of "citadels" built at places like Leith and Ayr. The citadel at Ayr is perhaps the best preserved, and here you can see an approach that combined "trace italienne" bastions with stone walls inspired by an earlier generation of castles.
The story of Scottish castles in the 1700s and since has largely followed the trend of movement from defence to comfort set in the 1600s. An added twist has been the widespread desire to reflect the earlier tradition of castles by building mansion houses that, either in overall form or in stylistic detail (or both), externally look and feel like castles. Hence the popularity of the "Scots Baronial" style; of castle-like towers; of battlements; and, in many cases, of the continued use of the word "castle" to describe what in many cases was now more of a mansion house. A further category of even more recent buildings comprises restored or rebuilt castle ruins such as those at Eilean Donan Castle and Kisimul Castle.
If Cromwell's citadels can be included in a description of Scottish castles, then one final structure is also worth mentioning. In the aftermath of the 1746 Jacobite uprising, the third major uprising in Scotland in less than 60 years, the Government took steps to ensure there would be no repetition. These included widespread suppression of real or imagined opposition, and political steps to win over the landowners and change the social factors that had fed rebellion. But their steps to avoid future uprising also included the building of the most ambitious and spectacular fortress ever constructed in the British Isles, at Fort George near Inverness.