The original word for tartan is French "tartaine" and this was originally defined as a type of material and not it's design or color. It was not until 1538 that the word tartan (stripes crossing at right angles) began to mean colored, checkered, marled, strided, mottled and sundrie colored. In the Gaelic the word was breaken, meaning checkered.
A tartan pattern is a simple two color pattern which is varied by the addition of overchecks, bands and stripes in contrasting colors. This process gives balance and symetry to the overall design. A simple two color check will give three colors, (if you overlap red and blue, you get purple; also yellow and blue generates green). Also, then, a pattern that calls for 6 colors will give you 21 shades of color.
Some scholars believe that the colored stripes may have been in response to the Irish custom of the striping of garments to indicate rank of the wearer. A high king had 7 stripes, one being purple. Amist all the controversy, we do know that the twill weave and the check pattern as we know today, were known in the 3rd century AD. Particular patterns or "setts" became common to particular localities first. These patterns prevailed over wide areas, were modified by tradition, local skills and the availibility of plants for dyeing the wool. These setts were modified by local weavers for their own ends. A length of tartan cloth was simply made up of one sett repeated over and over again until the desired length was achieved.
Original colors were acquired from natural sources, both mineral and plant. Because of soil conditions, there was much variation in shades of color. Various forms of litchens were used to create the reds, purples, yellows and browns. The red and purple colors were also obtained from lady's bedstraw, tormentil root, bramble, dandelion root, spindle and St. John's wort. Yellows came from birch leaves, browns from bog myrtle, greens from nettle, sorrel and ling and light yellow from flowering heather. Black could be obtained from natural wool or from alder bark, while blue came from indigo. In 1703 it was said that women were very careful to have colors and patterns be agreeable to the eye. Colors and patterns were notched or written on sticks. These sticks were used to preserve the true color and pattern of a sett. This concept of pattern sticks was also referred to when stories of ancient weavers were said to use "maide dalbh" or pattern sticks. None of these sticks have survived the period of proscription, 1745-1782 when the tartan was not permitted to be worn.
It was somewhere between 1411 and 1745 that the actual setts or patterns of the tartan began to identify some clan or military affiliation. As a certain clan or family would dominate an area or locality, within a district , the district tartan was more documented. In many cases the district tartan became a clan or family tartan. It was after proscription was lifted in 1782, that the move to give every tartan sett a name, either clan or district came into being. The thread counts were standardized at this time but the shade of color still remained an individual preference.
After proscription ended, native dyes were not plentiful enough for mass production and so foreign dyes (still made from vegetable matter) were used. These dyes produced the somewhat same effect as the native dyes did; the soft scarlets bordering on orange and rose colors, the varying light and olive greens, the blues from lights to copen, and the muddy yellows. These colors that represent the old or natural dye colors became known as "old" or "ancient" colors.
In the 1850's, because of demand for the tartan, dyes began to be made synthetically. These dyes were called anilines and this brought the color of the tartan into the era of the harsh tones; the dark blues and greens and the bright red we see today. Some of these greens and blues were so dark as to sometimes appear almost black, thus obscuring the original pattern or sett.
Reproduction (muted, weathered, faded) colors were introduced in 1946 with the idea of recreating the appearance of cloth that had been worn, weathered or stained with peat.
It must be borne in mind that color will vary from one dye lot to another and from one mill or weaver to another and therefore the only guide that is necessary is the pattern or set of the tartan.
The rebellion of 1745 has become a romantic adventure in the minds of many people and there still remains something mysterious about the tartan, the highlander and the Celts. This mystery pervades the imagination even today, for many people believe that the tartan is the heritage of all Celtic peoples, and we believe ,rightly so.