This a hardback book called "By Royal Appointment" a biography of Mary Ann Clarke (Mistress to the Duke of York) by Paul Berry; published by Femina Books in 1970 [pp. 235].

This copy is in very good unmarked condition for age with clean and tidy dust jacket.

Of all the famous mistresses, from Nell Gwynn and Emma Hamilton to Madame de Pompadour and Lily Langtry, Mary Ann Clarke was the most spectacular and the most outrageous. Her career was a rag-to-riches story of a girl from the teeming back streets of Georgian London who rose with premeditated guile to a life of pretentious affluence as the mistress of "The Brave Old Duke of York"...