Mary Venetia James (née Cavendish-Bentinck; 4 June 1861 – 2 May 1948) was a London society hostess and racehorse breeder.
In 1872, the 11-year-old Mary Venetia Cavendish-Bentinck had been a bridesmaid at the wedding of Christina Nilsson, a famous opera singer of the period.
Venetia held the bride's bouquet whilst Nilsson took her vows with her future husband, French banker Auguste Rouzaud.
She served her guests milk that her cat would not drink and preferred to host Catholics on Fridays because fish was cheaper than meat.
James died in 1948, without issue, leaving her jewellery and paintings by Titian, Joshua Reynolds and Thomas Gainsborough to her goddaughter, Queen Elizabeth.