Just for fun, here is another elusive one:
Colonel Bernard Ernest Jule(s) de Koetteritz.
He was in the service of the Russian Imperial Guard. He married Emma Bruce in Italy on 18 Oct 1849.
He was the son of a General de Koetteritz who lived at Leipzig, Brandenburg, Germany. I believe that he is going to have been born Bernhard Von Koetteritz in 1807 (at or near Brandenburg (Havel), Brandenburg, Preußen, Germany), with his parents being Con Koetteritz and Juliane. Not sure about that, though.
Do you see any reference to him? I have been completely unable to find anything but a document from a visit to England in the 1840s.