June is Pride Month, an annual celebration around the world of the LGBTQ+ community. An important symbol of Pride is the rainbow pride flag, with the colours of the rainbow commonly representing diversity in gay, lesbian and trans culture. To honour Pride celebrations, we take a look here at rainbows in medieval manuscripts and the colours used by scribes and artists to make them.

A drawing depicting the rainbow of Noah’s Covenant, from a roll copy of Peter of Poitier’s Compendium historiae in genealogia Christi, 2nd half of the 13th-century: Royal MS 14 B IX, 2nd membrane

The conventional seven colours of the rainbow may be best remembered in Britain by the mnemonic ‘Richard Of York Gave Battle In Vain’: R(ed), O(range), Y(ellow), G(reen), B(lue), I(ndigo), and V(iolet). Pigment colours used by scribes and illuminators were made from a variety of materials, including plants, minerals and animal sources. Ordinary dark writing ink was made from oak galls.

Many scribes prepared their own pigments, the colouring agent in paint. Pigments were made in a powder form, before being mixed with a binding medium such as glair (made with egg white), egg tempera (made with egg yolk), or gesso (a mixture containing gum).

An artist mixing colours in an inhabited initial opening the entry for ‘Color’, from James le Palmer’s Omne Bonum, c. 1360–c. 1375: Royal MS 6 E VI/2, f. 329r

Red and orange pigments were made with natural minerals, including a form of lead that when heated produces a vibrant orangey-red known as minium. Minium was commonly used to outline illuminations, giving the pictures in manuscripts the name ‘miniatures’ (not because they were small). Minium was a cheaper pigment in cost, and was also used in medicine and cosmetics.

The most common yellow pigment was made from a highly toxic substance containing arsenic, known as orpiment. Orpiment reflected light, similar to gold, but reacted easily to other pigments on the page. Yellow could be also produced organically from plant and mineral sources, including the luxury spice saffron that was imported from Persia and parts of Europe. Ochre was a cheaper alternative to saffron, and could be locally sourced in Bury St Edmunds, Oxford and the Forest of Dean.

A colourful diagram relating to music, in De artibus ac disciplinis liberalium litterarum by Cassiodorus, 9th–10th century: Harley MS 2637, f. 41v. This manuscript has been recently digitised by The Polonsky Foundation England and France Project, and on the Project website you can also read an article on Writing Music by Nicholas Bell. 

Artists could find recipes for pigments in written works such as the De diversis artibus of Theophilus Presbyter (fl. c. 1070–1125). The British Library holds the most complete copy of this treatise, containing instructions for painting, glassmaking and metalworking. It includes recipes for ‘Salt green’ and ‘Spanish green’, types of verdigris, a green pigment produced through a chemical reaction with copper. Verdigris was very corrosive and was often mixed with saffron to last longer on the page.

The opening of the recipe for Spanish green pigment, in De diversis artibus by Theophilus, late 12th or early 13th century: Harley MS 3915, f. 18v

Ultramarine blue was the most valuable pigment that artists could obtain, derived naturally from the mineral lapis lazuli. It was imported to Europe from Afghanistan and could cost as much as gold. Later medieval artists often used ultramarine blue for the robes of the Virgin Mary, saints and wealthy patrons to reflect their high status. A more affordable form of blue pigment known as citrimarine was manufactured from a copper compound called azurite. 

Deep blue or indigo was a plant-based pigment, likely obtained in Europe from the leaves of the woad plant. Indigo was used to complement gold leaf and used in night scenes in manuscript illuminations.

Violet or purple colours could be made from mixing red and blue pigments, or made from plants and lichens. One rich purple dye known as Tyrian purple was extremely valuable in the eastern Mediterranean, as it was extracted in tiny quantities from live sea snails, the mollusc murex brandaris. A precious pigment, Tyrian purple was used as a dye for the imperial robes of certain Roman emperors. The dye was also used to colour whole pages in high-status manuscripts.

A rainbow appears at the birth of St Fremund, from John Lydgate’s Lives of Sts Edmund and Fremund, 1434-1439: Harley MS 2278, f. 72v

Together all of these fantastic colours make the colours of the rainbow, so pretty in the sky and in illuminated manuscripts alike!

Alison Ray

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