I could find nothing about this person until I looked up Rheda Park, the name of a manor house near Frizington, Cumbria in the UK. This suggests the Dixons were minor gentry. It is located in a narrow part of the island of Great Britain near the island's west coast. The nearest major city is Leeds on the east coast. The Scottish border is close by with Lockerbie, the crash site of a terrorist bombing of a 747 airliner, not much farther north.
From highvictoriana.tumblr.com/post/40966189995/portrait-of-mrs-dixon-of-rheda-by-r-a-james; the image had numerous flaws that were fixed with Photoshop by gogm.