Marie-Louise Caroline Helene Williams

https://genealogics.org/getperson.php?personID=I00531962&tree=LEO

She was born Marie-Louise Freiin von Pfeffel to a German father von Pfeffel, but her name was entered into French records in a translated form as de Pfeffel. The Pfeffel family originates in Bavaria, Germany.

http://www.bbc.com/news/world-europe-42805485:

Five generations of von Pfeffels later, and we find Marie Luise von Pfeffel marrying one Stanley Fred Williams. Their daughter Yvonne married Osman Wilfred Johnson Kemal… and their son, Stanley Johnson, is British Foreign Secretary Boris Johnson's father.