Vince Guaraldi wrote this piece for A Charlie Brown Christmas, which first aired in 1965.

The MIDI file source for this song is hosted by The MIDI Farm.

I got the graphic of Schroeder from a United Media website and fixed it up condiderably.  Spelling Productions, Inc. currently owns the copyright to the Peanuts characters, but all the old properties are still owned by United Feature Syndicate.

Uhhh.... I lost track of where I found the background.