Great Works and their eras

Does anyone happen to know whether Great Artists/Musicians/Writers generate Great Works based on the era they were "born", or the era when their ability was used?

In other words, if I spawn a Great Artist in, say, the Medieval Era, deliberately wait until Renaissance, and then use him up for a Great Work, do I get a Medieval or a Renaissance work of Art?

Not done a lot of testing, but since at one point I had 4 Great Musicians just waiting for open slots. I can confirm they all made works for the era they were born in.

It's when the ability is used, NOT when it is born. You would get a renaissance work of art.

p.s. I've done this multiple times to get the Sistine Chapel and Uffizi filled up. I am 99.9% confident.

Great, thank you both for the answer =) I was hoping that was the case, because it makes theming a lot easier.