> The oldest still in effect copyright I know of is from 1611.
I can beat that by over 4000 years.
As far as Icelandic copyright law is concerned the copyright on the Diary of Merer[1], written 4500 years ago, will be held by the French Egyptologist Pierre Tallet until 2039.
This is because the copyright protection commerces when the work is made available for sale, loaning out etc. to the public.
If you discover a previously unpublished work that's not protected by copyright you get to enjoy 25 years of copyright protection, i.e. the copyright is assigned to the person who discovered and published the work.
I only have a source in Icelandic, it's article 44 of the copyright act [2].