Mary Jenkinson, Countess of Liverpool was the second wife of Robert Jenkinson, 2nd Earl of Liverpool who served as Prime Minister from 1812 to 1827.

Robert Banks Jenkinson, 2nd Earl of Liverpool, was a British Tory statesman who served as Prime Minister of the United Kingdom from 1812 to 1827. He also held many other important cabinet offices such as Foreign Secretary, Home Secretary and Secretary of State for War and the Colonies. He was also a member of the House of Lords and served as leader.