To our modern minds, the idea of not holding on tightly to one's own intellectual property is a complete anathema. By the same turn, artistic works that can't be indisputably attributed to a single named creator are mysteries to be solved rather than accepted. However, while plagiarism was beginning to become a concept during the seventeenth century, an artist was still only likely to see it as an important issue if they were planning to publish their works for commercial gain. If not, and if they were part of a collaborative family musical dynasty, it was much less of a thing to get hot under the collar about.
This is one of the best Christmas compilations for the classical music lover I know of, and far ahead of similar CDs from RCA Living Stereo, Nimbus, and Decca/London. Tracing over some 90 years of recorded sound, some of the highlights include: A nice, if somewhat saccherine, performance of "White Christmas" by, believe it or not, Nelson Eddy.