You may have heard of Beaumarchais. He was a watchmaker, publisher of Voltaire’s works, gun runner for the rebels in the American Revolution, but most notably a playwright of works such as The Barber of Seville (which Mozart adapted into an opera.)
In Beaumarchais’s time, writers were not well paid. The theatres of Paris held a kind of monopoly, or cartel. They colluded together to keep writers fees down.
The Barber of Seville was one of the hits of 1775, and continued bringing in audiences after that. But, despite the money that the theatres got from Beaumarchais’s popular play, his remuneration wasn’t very high.
So, in 1777, Beaumarchais led the other French writers in a strike. If they didn’t get paid more for their successful plays, they wouldn’t write at all.
This led to a scarcity of plays, and forced theatre owners into negotiations.
Theatre owners now paid royalties, instead of just a flat fee for plays.