what is the etymology of the theatrical term "green room?" what references support this etymology?

I understand it is because traditionally the walls were green (perhaps a "restful" colour?) but I have nothing to support this except Chambers which says just that. I have been in a few, and none has been green! Rgds, lusy

The lady I am currently living with, who happens to be my wife of 48 years past, has suddenly suggested that it may be to do with the practice in years long gone of covering the doors to the servants' quarters with green baize, as a soundproofing medium. What does the panel think of this? Rgds, lusy.

I have heard TV hosts say that this term came into use
because, for one of the first popular shows that had
guests appear, the room where they waited their turn
(and, presumably, tried to calm their nerves!) was green.

The Oxford Universal Dictionary, which describes green-room as "A room in a theatre for actors and acresses when not required on the stage, perhaps originally painted green", dates this word in 1701 (quite some time before television).

Danny Thomas