Yes, I'm aware of the patronage system. It's in use nowadays with the "Patreon" aspect of YouTube, whether it's reaction videos, livestream music concerts, or Shadiversity incorporating sponsorship products into his videos in an entertaining and dramatic way so as not to disrupt the flow of what he's talking about.
What I'm actually asking is (hypothetically): Once Michaelangelo was done with the Sistine Chapel ceiling, who owned that work? Michaelangelo or the Catholic Church? Could he have then gone on to paint someone else's ceiling with the same or related imagery and get paid for that as well, without objections from the church?
from what i read about IP pre industrial age/first IP things: the catholic church owned the work, because they owned the building, but they didn't own the rights to its likeness, no! noone did. so
technically he could just up and paint it again elsewhere. they could, as well! there were other mechanisms in play; difficulty of creation, and michelangelo's reputation as an artist. copying the ceiling by either party is both, importantly,
very difficult and would diminish its value for the church of having
a michelangelo work, as well as diminish the value for michelangelo's worth as a worker (who'll paint him for extravagant unique things if he just does it again elsewhere?). i don't know about north italy in particular, i want to stress, patents were introduced in venice in the 1400s, but if we talk about most of europe, this was the state of the world. owning rights to usage of likeness wasn't a thing.
it's like books before printing press. they could always be copied, honestly, so they were kept physically restricted in order to keep their value,
and copying a book was a tremendous undertaking anyways (which speaks to the worth of the first book to begin with), so copying a book didn't even diminish the value of the first one that much. and compared to a book, whose purpose was, still back then, containing information, doing that much work for something that just looked pretty didn't really make sense. they might as well hire an artist to do
something else pretty and unique. this was also before the idea of genius and high art classics mind you (in a sense), so it's not like "this art is a precipice of genius and civilization! i want one of the same too!"; rather, people
did enjoy the craftsmanship, they
did recognize that some art was special in a way, but our modern relationship to high art is relatively new; they didn't have this particular relation of genius to art. that kind of stuff mostly started in the enlightenment, and is quite kant's fault.
like, bach for example was just a minor, pretty good composer in his day. he remixed his own works all the time because he was basically just a practicing musician. our current repetoire of bach's works is a selection among his numerous iterations of his own works. he didn't really think of his pieces as platonic ideals of super makings set in stone. it was just good music. maybe great music. but that was it.