Lady Mary Coke was an English noblewoman born in 1725, known for her connections to the British royal family. She was the daughter of John Campbell, 4th Earl of Breadalbane and Lady Mary Villiers. Throughout her life, she was involved in the social and political circles of her time, often attending court events and gatherings. She is perhaps best remembered for her detailed diaries, which provide valuable insights into the life and customs of the 18th century British aristocracy. Lady Mary Coke's writings also reflect her opinions on various figures, including King George III and other prominent members of the nobility.