I came across this the other night: http://www.bbc.co.uk/programmes/b00zlgxz - it's a programme on the music of the court of the Holy Roman Emperor Maximilian I. I think he was late 15th/early 16th century, so possibly a bit late for DotS, but I suppose this could work if you don't already have something better for the HRE.
Actually there is a massive collection of world music on the BBC radio 3 website: http://www.bbc.co.uk/radio3/programm...layer/episodes - there are probably a few bits of medieval music in there somewhere. Are there any factions you still need music for?