It might be said that something in the way of Monumental Heraldry started in northern Britain in the later part of the first millennium BC with the aboriginal Picts - whose name is actually a Roman invention from the late third century AD. With the Z rods, moons, deer, elephant, salmon, cauldrons, mirrors and combs, ravens, axes and horses etc. that they cut into standing stones and monoliths, these ‘iron age’ Picts give us our first true glimpse of the use of monumental symbolism in northern Britain. Without a great deal more information, from other sources that are unlikely to have survived, it isn't possible to say that these inscriptions were hereditary or organized in ways analogous to heraldry in later centuries, but it is probably safe to say that they were used in many of the same ways: to mark out territorial ownership, as personal statements of identity, or as group markers of tribal identity (though perhaps in not quite the same way as a modern clan member's badge!)

By 503AD the Celtic Scots had entered northern Britain from the west and had begun to introduce Christianity to the aboriginal Picts. From this time on new forms of symbolism - griffins, dragons, knot work, vines, trees, all sorts of beasts and mythical creatures - began to be cut into new forms of monuments - monumental stone crosses and grave slabs, perhaps for much the same reasons that similar things were decorated heraldically in later centuries. 

The defeat of the Pict’s in 841AD by the Scots Celts and the unification of the two peoples under Kenneth MacAlpin in 843AD saw the the ‘Stone of Destiny’, the symbolic and metaphoric seat of power of the Celtic Dalriadic Kings, moved to Scone in the old Pictish kingdom, which was to become the centre of government, a real seat of power in Scotland with the birth of a Scottish nation of diverse peoples – a nation which continued to be diverse in its origins and traditions, as the heraldry of later centuries records.

Although there is no definite and clear start date for heraldry as we know it today in Scotland, it had certainly been established by the later part of the 12^th century and although growing in use, as can be seen from 12^th century seals, that growth and development was sadly poorly documented in the remains that have come down to us.

Within a century or so of the establishment of heraldry in Scotland the long struggle against English imperialism had begun with the invasion under England's Edward II and the start of the Wars of Independence. Things were to calm down for a while with victory at Stirling Bridge, but it took eight years of struggle from the crowning of Robert Bruce in 1306 until English military occupation was definitively ended at Bannockburn.

Whatever heraldic records there were in those times, whether in Scotland or stolen away by the former occupying power, have long since vanished and all we are left with are the seals and monuments. And this, unfortunately, remains true of Scots heraldry through medieval, Renaissance and Reformation times, as much of the written and painted record has either gone in the flames of unfortunate fires or was stolen away in a later English military occupation, the one of the 1650s.

But although we lack the written and painted records, what we do have, as we have for the Picts, is the records of the monument in stone and, which we don't have for the Picts, the carvings in the much more perishable medium of wood.