The Duchess of Duker

I have the clearest memory of standing in the kitchen telling Stefan that the Duchess of Duker von Meyer (which sounds like the perfect beginning to a music hall song) was the wife of a man who was ennobled after the Battle of Waterloo, with personal intervention of the Duke of Wellington.

I know I must have dreamed it, but it doesn't feel like a dream. Were the Germans involved anyway? (see the depth of my knowledge?)

Triggered by receiving a photo of the Duchess's necklace from a Schmelitschek cousin, Rowley Foster, whose mother wore it on her wedding day. I think she is to be coaxed for further memories and family tales.