Breacan (BRECH-kan), tartan, the cloth of plaids, is one of the most recognisable visual systems in the world and one of the most misunderstood. In its popular form it has been reduced to a nationalist shorthand sold in airport shops and applied indiscriminately to tea towels.

Underneath the kitsch is something genuinely interesting: a sophisticated system of colour coding and visual identity that predates most of what we call modern graphic design by several centuries.

Tartan is, structurally, a woven colour grid. Coloured warp threads cross coloured weft threads at right angles, and every intersection produces a colour that is a visual mixture of the two crossing threads. The pattern is defined by its sett: the threading sequence, the specific arrangement of colours and thread counts that, repeated across the width and length of the cloth, generates the tartan structure.

How a sett works

The sett is the generative code. It is written as a sequence of colour abbreviations and thread counts, and when that sequence is woven against itself at right angles, the crossing produces the pattern of squares and diagonals that is the tartan grid.

The elegance of it is that a simple linear code produces a complex two-dimensional result. The colour at any given intersection is not purely one thread colour or the other but a visual mixture. Red crossing green reads as brownish-ochre or dark olive depending on proportion. The tartan designer is not designing individual colours. They are designing colour interactions: specifying a sequence and predicting how it will combine when it crosses itself.

This is colour theory in its most practical and most constrained form.

Note on setts: specific thread counts vary between registered and historical versions of the same tartan. Check any sett against the Scottish Register of Tartans before quoting it, which is free and searchable.

The dyes

The palette of traditional tartan was limited by what natural dyestuffs would give on wool:

  • Crotal (KROH-tul), lichen, for the warm ochre-brown that characterises the oldest surviving fragments
  • Madder (madar, MAD-ar) for red
  • Woad (guirmean, GOOR-uh-man) for blue
  • Weld, Reseda luteola, for yellow. Note that weld and woad are entirely different plants; weld is dyer's rocket and gives yellow, woad is Isatis tinctoria and gives blue
  • Oak gall with an iron mordant for black

Crotal deserves particular attention. It is a mordant-free dye: the colour fixes directly in the wool without a metallic mordant to set it, making it the simplest and most accessible of the traditional Scottish dyes. It gives a warm muted ochre-brown ranging from sandy gold to deep russet depending on the lichen species and the wool.

That colour is the characteristic tone of undyed-seeming Highland cloth, and it is the colour of the ground itself: heather, peat, autumn grass. Old tartans, particularly those predating the aniline revolution of the nineteenth century, read as belonging to the land rather than imposed on it.

One caution that the romance tends to omit. Lichens grow at a rate measured in millimetres per year, and some of the species used for crotal take decades to establish. Stripping a rock face for dye removes centuries of growth. If you dye with crotal, gather fallen material or gather very lightly, and know what you are taking.

The dye plants have their own article on this site.

The history

The word tartan is of uncertain origin. Possibly Old French tiretaine, a type of cloth. Possibly Scottish Gaelic tarsainn (TAR-shin), across or crosswise, describing the crossing of the weave. The cloth is attested in Scotland from at least the sixteenth century.

Most modern clan tartan attributions descend from a forgery. The Vestiarium Scoticum, published in 1842 by the brothers who styled themselves Sobieski Stuart, claimed to reproduce clan-specific tartans from a medieval manuscript. There was no manuscript. It is the source of a great deal of what is now sold as ancient clan tradition.

The genuine history before the nineteenth century is more interesting than the invented one. The evidence points to district tartans rather than clan tartans: patterns associated with regions, woven by local weavers from locally available wool and dye, varying by place rather than by surname. The Highland weaver did not consult a register. She wove what she knew, from what grew nearby.

The féileadh mòr (FAY-lugh MORE), the great kilt, that a Highland man wore before the Act of Proscription of 1746 would have been in whatever pattern his local weaver produced. That might have been associated with his clan's territory, not because a heraldic authority had registered it, but because a weaver in that glen wove that sett.

The Act of Proscription banned Highland dress, with the Dress Act provisions taking effect in 1747 and remaining until repeal in 1782. Along with the disarming and the suppression of the pipes, it belongs to the same programme of dismantling that this site discusses in The Silences. When tartan came back it came back through the Highland regiments and then through the Victorian romance of Scotland, which is precisely why the nineteenth-century inventions took so completely: there was a gap where the tradition had been, and something was going to fill it.

The visual grammar

Setting aside the clan mythology, what is genuinely interesting is tartan's consistent readable structure.

Ground and overcheck. A tartan is characterised by its ground colour, the dominant tone, usually the largest thread count in the sett, and its overcheck colours, the crossing bands in smaller counts that create accent lines.

Pivot and symmetry. Most tartans use a pivoting sett: a sequence that reads the same forwards and backwards, mirroring around a pivot point. That symmetry produces the diagonal lines running at forty-five degrees through the grid, which are the visual signature of the form.

Colour relationships. The art is the management of intersections. Where contrasting colours cross, the intersection creates a third visual colour that is not specified anywhere in the sett. White crossing green reads as pale sage. Red crossing blue reads as dark purple-maroon. The final effect is the sum of all these emergent colours, which is why the same sett in different base colours produces a dramatically different cloth.

Modern tartans. The Scottish Register of Tartans records thousands of patterns: corporate, regional, commemorative, personal. Contemporary designers work within the same structural system with a full modern colour range, from muted traditional tones to deliberately synthetic palettes pushing against the symmetrical grid.

Identity encoded as structure

What makes tartan remarkable as design is that it encodes identity through structure rather than through image.

A clan tartan does not depict the clan. It contains no symbol, no coat of arms, no representational element at all. It simply is a particular arrangement of coloured threads: a sett different from every other sett and therefore readable as a specific identity. The identity is in the pattern itself.

That is a sophisticated approach to visual identity and it has influenced contemporary branding and textile design in ways rarely acknowledged. The idea that arrangement alone carries meaning, independent of symbolic content, describes the logic of a great many successful identity systems, from Islamic geometric ornament to Mondrian's grids.

The breacan a Highland man wore was not merely warmth. It was identity made visible in the most fundamental way available: woven into the structure of the thing itself, inseparable from it, and identical with the pattern his community recognised as its own.

A note on the Gaelic in this article: the terms above have been checked against Am Faclair Beag where possible, and pronunciations are approximations for English readers rather than IPA. Some tartan-weaving vocabulary is not well recorded in Gaelic dictionaries and I have not included terms I could not verify. Corrections welcome.

Sources

  • Scottish Register of Tartans, the official register. Free, searchable, and the place to verify any sett.
  • Cheape, H. (1991, rev. 2006). Tartan: The Highland Habit. National Museums Scotland. The scholarly account, and the corrective to the popular history.
  • Cheape, H. on the Vestiarium Scoticum and the invention of clan tartan.
  • Trevor-Roper, H. (1983). The Invention of Tradition: The Highland Tradition of Scotland. In Hobsbawm & Ranger (eds.), The Invention of Tradition. Cambridge University Press. Contentious, overstated in places, and essential.
  • Sobieski Stuart, J. S. & C. E. (1842). Vestiarium Scoticum. The forgery itself, available via Internet Archive.
  • Act of Proscription 1746 and the Dress Act provisions, in force 1747 to 1782.
  • Grierson, S. (1986). The Colour Cauldron: The History and Use of Natural Dyes in Scotland. The book on Scottish natural dyeing, and the source for crotal, madder and woad practice.
  • Milliken, W. & Bridgewater, S. (2004). Flora Celtica: Plants and People in Scotland. Birlinn.
  • Am Faclair Beag for the Gaelic.
  • On lichen conservation, British Lichen Society and Plantlife.

Related: [Crotal, Woad and Madder]; [The Silences]; [The Palette]; [The Scottish Colourists]; [How to Read an Esoteric Claim]