And for extra credit, when did bands start identifying as a group rather than by the talent of a single musician?
The Richardson Rock Band in 1842 is the oldest name I know of. Joseph Richardson was a stone mason who spent year painstakingly collecting rocks and build a gigantic stone xylophone. It took three people to play it, thus the Richardson Rock Band is born. It may not be your classical definition of a band but they were quite popular and had spawned a movement of rock based music in England.
http://www.npr.org/templates/story/story.php?storyId=5445541
The NPR article is quite short but the audio link still works. I would highly advise listening through the whole piece as Richardson stone xylophone is available to the public and they end the piece with a recording of someone playing the 175 year old instrument. They link to Collins' original article which is an interesting read but the audio piece has the most details.