Jack, I'm going to have to protest that Ravenscroft is "well past medieval". A book published in 1609 contains songs well established in the years prior and the renaissance didn't start at the same time throughout the world. The fact that we as a society regularly sing songs from the 1800's and 1900's offers a very valid argument that a songbook published in 1609...when songs were predominantly learned from generation to generation through oral tradition...would contain songs from the 1500's and 1400's.