Greetings! One of the best experts on such matters is Prof. Wright, and that's his website: https://www.nottingham.ac.uk/music/people/p.a.wright - You should possibly contact him.
Kretschmer, Martin, and Friedemann Kawohl. "The history & philosophy of copyright." (2004): 21-53.
Kretschmer, Martin. "Intellectual property in music: A historical analysis of rhetoric and institutional practices∗." Studies in Cultures, Organizations and Societies 6.2 (2000): 197-223.
Ginsburg, Jane C. "“Une chose publique ? The author's domain and the public domain in early British French and US Copyright Law" The Cambridge Law Journal 65.03 (2006): 636-670.
This is interesting, thanks. For my forthcoming project I'm more interested in the commercial/legal/publisher side of things than the creative musical input or philosophical considerations of authenticity etc - which I find fascinating, I might add. But thank you for sharing this, which is thought-provoking.