When the Romans invaded Britain, they were confronted by warriors who had painted their bodies blue. The name they were given, “Picts”, actually means painted ones. It was believed that they used dye extracted from the woad plant to dye their skin and to tattoo it. Reports state that the woad was mixed with stale human urine in order to get it to stain the skin more visibly and to stay on the skin longer. But what was woad, and was it really used to dye the skin of ancient warriors?
Woad is a flowering plant that was found in many parts of Europe and Asia. Once it was found to have use as a dye it was cultivated in many other areas and can now be found throughout most if not all of Europe. When woad plants are processed, they produce indigo, a natural dye that colors fabric blue. While it is the same chemical as that produced by “true indigo” plants, the color is different than those produced by “true indigo”. The color was so superior that woad-dyed fabric became part of sumptuary laws and was reserved for royalty.
To extract the dye from woad, the leaves were stripped from the plant. This was normally done in July and August. The leaves were torn into pieces and steeped in water that was hot but not boiling. The water was cooled and the leaves strained out. The mixture needed to have something added to it in order to raise the pH. This needed to be done when the liquid was at the right temperature or it could destroy the blue pigment. The mixture needed to have air added to it and then it needed to sit in order to let the dye settle out. It could then be added to fabric in order to dye it or it could be dried in order to store it.
Woad is also used in other cultures for reasons that have nothing to do with dying fabric. For example, it can also be used to make tea that can treat a wide range of medical conditions including sore throats, influenza, measles and several other diseases. It is also used as a preventative for other medical conditions such as epidemic meningitis, certain types of hepatitis and some types of cancer. The tea is made from the roots, not the leaves.
But was it used to dye skin? Many individuals who take part in medieval recreations do use woad to dye their skin. It is capable of tinting the skin and takes some time to fade. It is caustic, however, and if it is put on incorrectly or used to tattoo the skin, it can burn it. The skin would have a very difficult time healing properly if woad was used to color or tattoo the skin. It also tends to flake off of the skin when it is applied incorrectly.
Woad is still being grown for a variety of reasons. Many cultures still use it to dye fabric although they do not do it as frequently as they did in the past. Woad is also being used in the production of printer ink. Despite its popularity, some countries have declared it to be a noxious weed and are actively attempting to eradicate it.