The painting is in Balnagown Castle in the Scottish highlands that was, according to a Wikipedia article, the seat of the Clan Ross Chieftains. It is now owned by Mohamed Al-Fayed who lost his son Dodi in 1997 during a high speed car chase in a Paris tunnel with paparazzi pursuing Dodi and his girlfriend Diana Spencer.
From Wikimedia; numerous spots throughout image removed with Photoshop and lightness added to image by gogm sufficient to show her coiffure against the dark background.