SU8504 : Scratched lettering
taken 2 years ago, near to Chichester, West Sussex, England

Many churches have, scratched in the stone, patterns of circles, crosses, and mystic signs. After literacy became more common, names and dates started to appear.
The name 'medieval graffiti' has been given to these vernacular carvings, but some of the dated ones have 17th and 18th century origins, and I have seen one dated 1952.
It has been suggested that these represent an attempt to associate people with the place, in the hope of a safe return from pilgrimage or war. No-one really knows. It may simply be the same determination to 'make one's mark' that led schoolboys to carve their desks, or modern youth to get out the spray paint. But some of them must have taken a lot of time to complete, perhaps in more than one session, suggesting that the local church authorities were tolerant of this practice, that it was culturally normal.
The phenomenon is not unique to churches, as roadside crosses sometimes fall victim. Curiously it does seem to be confined to stonework of communal ownership, you don't see it done on people's homes or gravestones.
There is a web site called "Medieval Graffiti" which is owned by a project recording the phenomenon in Norfolk, but similar carvings have been found all over the country, although largely ignored by historians up to now.
Norfolk: Link
Suffolk: Link
Lincolnshire: Link
Surrey: Link
East Sussex: Link
Derbyshire and Nottinghamshire: Link
BBC story: Link
Blog: Link