In other cases, blue and purple were used to depict monstrosity, as in the iconic image from the Luttrell Psalter, where Richard the Lionheart fights Saladin, a purple-skinned, big-lipped, hook-nosed monster.

XREF: Connects to the broader history of color symbolism in medieval art and the cost/availability of blue pigments like ultramarine.

Sophia Rose Arjana, Muslims in the Western Imag…, loc. 106