Mary Curzon, 2nd Baroness Ravensdale

Mary Irene Curzon, 2nd Baroness Ravensdale, CBE (20 January 1896 – 9 February 1966) was the eldest child of George Curzon, 1st Marquess Curzon of Kedleston and Mary Victoria Leiter, a daughter of Levi Ziegler Leiter.

She inherited her father's Barony of Ravensdale, County Derby, in the Peerage of the United Kingdom, on 20 March 1925, and was created a life peer as Baroness Ravensdale of Kedleston, of Kedleston, in the County of Derby on 6 October 1958. This allowed her to sit in the House of Lords prior to the passing of the Peerage Act 1963, which allowed suo jure hereditary peeresses to enter. She and her two younger sisters were memorialized by Anne de Courcy in The Viceroy's Daughters: the Lives of the Curzon Sisters.

Curzon had an intimate insight into the life of the Duke of Windsor, his friendship and marriage to Wallis Simpson and the life of the House of Windsor, herself and through her sister, Alexandra and her brother-in-law Major Edward Dudley Metcalfe, best friend of Edward VIII. She saw the rise of British fascism through her sister Lady Cynthia Mosley and her other brother-in-law Sir Oswald Mosley, with whom she had an affair prior to their marriage.