An illuminated letter is an embellished letter found in illuminated manuscripts from the Middle Ages that features extensive decoration and color. The Book of Kells from 800 AD is considered the finest surviving example, containing elaborate illustrations and ornamentation incorporated into capital letters at the start of chapters and verses. It was created by Irish monks, stolen by Vikings, and later recovered from a bog where it was preserved by the acidic conditions. Illuminated letters combined imagery from nature and Christian symbolism to beautifully decorate sacred texts.