This is one aspect of art that was just as bad in those days as it is now, perhaps even worse...I bring this curiosity to you courtesy of Deacon Paul Iacono of the Fra Angelico Institute of Sacred Arts. He, in turn, drew on reports that appear in the Guardian newspaper, here. As part of a systematic study of graffiti in Churches in East Anglia they have found some signed by a writer and monk John Lydgate (an admirer and friend of Chaucer). What strikes me about all of these is how timeless the images are. Graffiti, it seems was just a bad (or good, depending on how you look at it) in the 14th century as it is now! To the left you have a bishop in mitre. Below is an inscription found in St Mary's church, Lidgate, Suffolk. The text on the pillar, a few millimetres high, translates from the Latin as 'John Lydgate made this on the day of St Simon and St Jude'. That feast day is 28 October, with the year some time between 1390 and 1450. Underneath that is the church where the inscription was found. Other examples include devils or dragons and even geometric patterns.
Given the great interest in these, it does make one wonder if the past whitewashing of graffiti in the New York subway might be seen as a destructive act of iconoclasm by future commentators!
This looks like a dragon or a devil
Below, a montage of various compass drawn designs: