I WROTE last week about the enduring mystery of Scotland’s prehistoric standing stones and showed how their erection at various sites around the country may have had something to do with astronomy or religious observances or possibly even fertility rites.

The truth is, however, that we just do not know for certain why the stones at, say, Calanais on Lewis and the Ring of Brodgar on Orkney, were erected thousands of years ago. Their origins are truly mysterious and will likely remain so.

Normally, as we who write about Scottish history soon get to know, the nearer events or people are to our own time, the more there is to discover, and we are able to write about things with authority. In Scotland’s case that includes as far back as the era of the Roman Empire and its brief and ultimately unsuccessful occupation of this country, which really was the last outpost of that vast empire in the early part of the first millennium.

We know what the Romans thought of us, and indeed they coined the name “Picti” meaning painted people – think Mel Gibson’s woad look in Braveheart.

Yet the Romans do not tell us much about the Picts, and it is not until the latter half of the first millennium that they appear again in written history – but with precious few details about the tribe. That is why the existence of Pictish standing stones is arguably one of the greatest mysteries in Scotland’s entire history.

Despite more archaeological discoveries about them in recent years, the Picts who flourished in the east and north of this country for centuries mostly remain a mystery to us, principally because we do not know their origins or their language.

The latest research, published only last month, shows that the Picts were indeed the original occupants of much of what is now Scotland north of the Forth and Clyde, and they were not immigrants from elsewhere in Europe as had been previously thought by some.

The Picts remain a fascination to historians, scientists and the public alike simply because we know so little about them – or indeed what happened to them when the Scots and Picts united under King Kenneth MacAlpin in the 840s.

There is a small possibility that MacAlpin and his successors conquered the Picts militarily, but I have always preferred the version that the two tribes merged peacefully through intermarriage.

All we can say is that the Picts faded into near-oblivion by the end of the first millennium and left us very few clues about their existence and culture. But some of those tantalising clues are provided by their standing stones.

There are more than 300 stones classed as Pictish, mainly across the north-east. They used to be always divided into three “classes” thanks to researchers in the early 20th century but more modern investigations have shown such a classification to be simplistic, although the division into “classes” is still used, usually to date a stone – Class I is the earliest and Class III the most recent, dating to around the eighth to ninth centuries.

Unlike the prehistoric stones, there is no equivalent of these Class IIIs anywhere else in the British Isles – they are uniquely Pictish. Many of those which have survived the erosion of the centuries have symbols representing animals and items of culture such as mirrors and combs which the Picts were known to treasure.

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Several of the stones have symbols that occur in the very rare examples of Pictish jewellery which have been found, proving that the stones were indeed the creation of Picts.

Thanks to the general absence of recognisable writing – though some do have inscriptions in Ogham, an early medieval alphabet – why they were erected is not often known, and some now lie recumbent and not in their original position. How that came to happen is again a mystery and cannot be blamed on Christians tearing down pagan objects because the Picts themselves were largely Christianised from the sixth to the ninth centuries – St Columba was the first missionary to the Picts recorded in history – and this is the period to which most of the stones can be traced.

I will be devoting much of this column to the four stones at Aberlemno in Angus, arguably the most researched such stones in the country which are in the care of Historic Environment Scotland (HES) to whom I am greatly indebted for much of the information in this column.

HES is in no doubt about the importance of Pictish stones, stating: “Evidence for the Picts predominantly comes from their art, and particularly from carved stones. These carved stones are clearly products of accomplished sculptors and may provide evidence of a structured society. Skilled sculptors must have been commissioned to create these masterpieces, most probably at the behest of the Pictish elite.

With the lack of other significant evidence for the Picts, these carved stones therefore give an insight into Pictish society, foreign contacts and cultural resources.”

First of all, however, before Aberlemno I want to deal with several other Pictish stones that are well known. The Maiden Stone near Inverurie in Aberdeenshire is a

well-preserved red granite stone standing more than three metres tall. It has a mixture of Pictish and Christian symbols – notably two fish which could be Jonah’s whale – and probably dates from the late eighth or early ninth century. It has suffered some erosion and is missing a triangular notch at the top.

Local legend has it that a laird’s daughter made a bet with a stranger that she could bake a bannock quicker than he could build a road to the top of Bennachie, with her hand in marriage if she lost. However, the stranger was the devil in disguise and won the bet.

The woman ran away and prayed to God to save her from hell. God turned her to stone on the spot, the notch being where the devil grabbed her even as she was petrified. A myth, of course, but it shows how Christian and Pictish legends were mixed in the Maiden Stone.

The Dunnichen Stone is truly fascinating. Carved from red sandstone and dating to the early seventh century, this stone was found in 1811 near Dunnichen in Angus. Having been removed to Forfar via Dundee, a replica now stands at Dunnichen. It has Pictish symbols including a rare flower and though only 1.5m tall it is a beautiful piece of work which truly demonstrates that the Picts were a cultured and artistic people.

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Possibly the most famous of all individual Pictish stones, and certainly the largest, is Sueno’s Stone which is located near Forres in Moray and which is now encased in glass to preserve it.

This stone is intricately carved with both Pictish and Scottish symbols and representations of troops in battle. It is thought this giant piece of much-weathered sandstone may have been erected to commemorate the legendary defeat of invader Sweyn Forkbeard by King Malcolm II, but that cannot be stated with certainty as the stone may well pre-date Malcolm’s reign.

More likely is the interpretation that the stone was raised to mark the victory of the Scoto-Pict army of Kenneth MacAlpin over the men of the far north, perhaps Vikings. Whatever its origins, it is a stunning monument on a site that can be visited all year round.

And so to Aberlemno which has four stones from various periods from 500 to 800, three of them standing by a road and the other in the village churchyard.

ACCORDING to HES, they comprise: a leaning, re-used prehistoric standing stone; an unshaped boulder bearing traces of two symbols; a magnificent cross-slab; and a sandstone cross-slab in the churchyard. HES states: “The stones show a range of carvings, from characteristic Pictish symbols to overtly Christian iconography.”

Identified as Aberlemno II, the churchyard cross-slab is one of the best-preserved of all Pictish stones. In its Statement of National Significance, HES says: “It may be said to represent the highpoint of lowland insular fusion in Pictish art, likely carved in the late eighth century, exhibiting some of the most complex of all knotwork on a Pictish carved stone. It is perhaps the finest cross-slab in its class.

“Other than a partially drilled hole and a fully drilled hole through the upper portion of this cross-slab, the latter perhaps to aid in the movement of the stone, it stands as one of the most complete of all Class II Pictish carved stones. Its current excellent state of survival allows for it to be one of the most easily experienced Pictish stones, although not necessarily the easiest to interpret.

“Its quality of carving, in both relief and incision, and the variety of motifs and styles present, highlighting both Celtic and Anglian tradition, demonstrates the cultural significance of this Pictish stone. This stone communicates to us that the Picts were not an isolated or primitive culture.

“This cross-slab demonstrates advances in the technical and architectural knowledge of the Picts, as is evident in its pediment, tapered sides and the impressive cutback that better reveals the cross.

“This stone is one of a very few Pictish symbol stones to depict a battle scene. It is interpreted as symbolising a battle between the Picts and the Angles, and usually thought of as representing the Battle of Nechtansmere (or Dunnichen) in 685 AD, where the Picts were victorious.

“However, this once ‘seductive idea’ is now unlikely, as the battle location is now thought of as being in northern Pictland. Nonetheless, its rarity in this sense attests to its cultural significance, particularly as its iconography allows for a window into Pictish society and the Picts tumultuous relationship with the Angles, as well as also perhaps with the Vikings.

“It is an explicit expression of Christianity in southern Pictland. The mixing of Pictish symbols and Christian iconography on this cross-slab is deliberate, and therefore perhaps designed to convey complex messages during a time of conversion.”

Aberlemno I is the northernmost of the three stones by the roadside and is an exceptional example of a Pictish symbol stone.

HES says of the stone: “It stands out in the archaeological record as a near perfect surviving example of Pictish art on stone.

“Its completeness and state of preservation are of great importance to its current and future potential in research and education.

“Considered as part of the Aberlemno group the stones can demonstrate the evolution of Pictish carving from Class I to Class III.”

In other words, it is a record in stone of how the Picts developed, and it is a remarkable example of how the Picts took an existing standing stone from the prehistoric era and transformed it with their own art.

HES says: “The stone more than likely stands in its original location on a prominent ridge, perhaps signifying the location of a major route way, which now connects the modern areas of Forfar and Brechin.

“It has been stated that we should ‘not lose the ability to recognise this on the ground’, thus highlighting the significance of this stone’s landscape setting, both immediate and beyond, as well as past and present.

“This symbol stone perhaps had a role as a boundary marker and would have been erected under the patronage of secular or ecclesiastical aristocracy.

“Due to the clarity and confidence of the carvings on Aberlemno I, it therefore has the potential to clearly highlight and identify some of the various differing symbols within Pictish art – a pictorial language unique to Pictland during the early medieval period.”

Though they are a genuine Scottish mystery, all the Pictish standing stones tell us one thing: that our ancient ancestors were a proud and independent people of culture. Why not try to be that again?