Good question, I know access to dyes was directly tied to ease of access and cost of access. There was limited color home dyes and then professional guilds for dyeing clothe.Certain colours were very expensive to create and others less so.
We know purple was a protected color and reasonably given to only those with means, such as royalty.
Red can be created several ways and bright red would have been in great demand but strictly limited in use to higher ups in the medievel period. Red represented blood and the power of life and death and was used almost exclusively by nobility and their institutions and the church. Also to get alot of clothe dyed red would have been very expensive and difficult. Thats why they were of such importance and value in trade and commerce. Embroidery would have been the less expensive way to add color and in limited amounts. Ribbons and thread of red would have been more common.
Dyes from Plants:
Weld - Yellow. Native to Northern Europe. Weld seeds have been found in various archaeological sites.
Dyer's Greenweed - Yellow, same chemical as weld (luteolin). Native to Northern Europe. Luteolin has been identified in Medieval textiles.
Buckthorn berries - Yellow, native to Europe. Mentioned in Medieval texts.
Safflower - yellow and pink. Native to Asia. Very common in Eastern textiles and Egypt, not as common in Europe.
Saffron - yellow. Native to Asia. Used extensively through the Middle East and Spain. There is some contention as to whether "saffron" Irish leinte were actually dyed with saffron or just looked the color of saffron.
Madder - Reds from roots. Native to Middle East, spread to northern Europe before 1066. Very fast dye; has been identified in many Medieval and Renaissance textiles. England was famous for it's madder reds in the 14th C., Turkey red was also madder-based.
Brazilwood (sappanwood) - Reds from heartwood. Native to Asia, spread to northern Europe before 1200. Often used in combination with madder because of its tendency to fade. Brazil was named for the trees, not vice versa!
Woad - Blue. Native to Northern Europe. Famous as the blue used by Celts for body-paint. Woad seeds were found in Medieval archaeological sites. Woad is a vat dye - a fermentation process must be used to fix the colors.
Indigo - Blue. Native to Middle East. Same chemical as woad (indigotin) but in greater quantities; same sort of dye process. Laws were passed in England to prevent indigo use to protect the woad industry.
Alkanet - Purple and grey. Native to Southern Europe. Also used as a red food dye.
Logwood - Purple and black (with other dyes). Native to Asia. Logwood didn't seem to gain popularity until 16-17th Century, but then became a very common black dye.
Dyes from Fungus:
Various mushrooms - Almost every color you can imagine. Most mushrooms yield yellows or dull browns, but some varieties yield blues, greens, reds, oranges, purples, and other colors. Difficult to impossible to tell if they were used historically.
Lichens - Range of colors; purple, orange, shades of tan and brown are most common. Lichens are actually a symbiotic arrangement between and algae and a fungus. Different lichens are native to different areas. Orchil, or purple lichen, has been positively identified in some Medieval finds.
Dyes from Animals:
Murex purple - purples, reds, and blue-violets from molluscs. The chemical components of mollusc dyes are very similar to indigo.
Kermes, lac and cochineal - brilliant reds and purples from bugs. Kermes is native to Southern Europe, Lac to the far east, and various cochineals to Poland and parts of the Americas
The Emperor alone was allowed to wear purple robes during Roman times. Senators had to make do with purple ribbons on their togas. German emperors continued the tradition of wearing purple robes as a symbol of power and they were joined by the cardinals in 1468.
Strict clothing regulations were enforced in Europe up to the times of the French Revolution. Pure colors were reserved exclusively for the rich nobility. Preparation of pure bright colors from natural sources was very tedious. Development of complex technical processes such as extracting of carmine from the cochineal insects or red dyes from the madder plant made it finally possible to achieve bright red tones. Wearing red coats was the exclusive right of the nobility in medieval times and the red robes of kings, cardinals, judges and executioners announced their power over life and death.
Advent of modern dyeing procedures and deteriorating power of the nobility led to the demise of red as a symbol of power. Red military uniforms became common up to the 19th century, Today's Judges on the Supreme Court in Germany wear red robes.
Sourced from various internet sources and my mom who was a fashion designer and dyer of all kinds of things, nothing stayed the same color when we were kids!!.
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