I was reading an article this week about the only known palimpsest that effaced the Bible to create a copy of the Koran. Which got me wondering about the oldest known palimpsest.
A quick note for those of you who don’t read a lot about religious history: a palimpsest is any document in which the original text has been scraped off and replaced with a later text and in which the original text may be read — in the days before technology, this often had to be done by eye, but now technology allows for the original text to be read more easily and without damaging the current text. Palimpsests are often religious in nature — the largest collection (around 130 texts) is at Saint Catherine’s Monastery in Egypt — particularly on the surface text, but don’t necessarily have to be. Palimpsests are usually written on parchment, though some have appeared on paper or papyrus. The reason parchment is the most frequent source of palimpsests is a combination of both its durability and its cost. Because parchments were expensive and in short supply and because they were durable, the original writing could be stripped from the medium (using oat bran and milk) and a new document could be written over top.
As for the oldest known palimpsest, this is a bit tricky. Of the known palimpsests, many — including the Archimedes Palimpsest — originated in the 4th – 6th and 9th and 10th centuries BCE. From what I can find, the oldest is a second century BCE Greek grammar text produced for the Roman Emperor Marcus Aurelius, which is housed in Vienna.