Monasticism was a way of life in which individuals gathered together to spend their days in prayer and self-denial. Monks were common during the Medieval Period. They separated themselves from the warfare and chaos around them to devote their lives to holiness. They built monasteries like this Monastery of San Juan de la Peña in northern Spain, deep in the forests covering the foothills of the Pyrenees and tucked away from the rest of the world.
It was built right into the cliff side. The outside looked like a fortress, and the inside was mostly dark and only lit by torches. There was an upper story that opened to a cloister (an open court or garden surrounded by a walkway) next to the cliff overhead.
In these monasteries, the primary activity of monks was copying ancient texts (usually the Bible). These had to be done by hand, since this is before the printing press. The monks wrote their books in Latin. Along with hand-copied books, manuscript illuminations became the most important paintings in Europe for a thousand years. They are the most classic example of Early Medieval art. Manuscripts were decorated with gold and silver leaf, and for those who could not read the text (since, as I mentioned earlier, literacy was quite low), illustrations were put in. A typical example of an illuminated manuscript looks something like this.