Lord Shelburne leased Streatham Park from Hester Thrale after the death of Henry Thrale. He used Streatham Park as his country residence as he had a home in London, Lansdowne House, a magnificent mansion built by Robert Adams. Dr. Johnson and David Garrick were some of the famous people of the day who frequented his literary gatherings. The house still stands in Fitzmaurice Place in Mayfair though much altered. It is now the Lansdowne Club.
Lord Shelburne was the Prime Minister from 4th July 1782 until 2nd April 1783. He was very unpopular because of his support for the American colonists in the American War of Independence. While living at Streatham Park he drew up the Treaty of Paris, the peace treaty that brought the American War of Independence to an end. This Treaty made him very unpopular with the British public and he was forced to resign as Prime minister.