 Dunwich in Suffolk, his constituency, was a pocket borough, controlled by the Downing land-owning family; Barne, the local Vanneck family and the freemen of the borough slowly ousted the Downings' influence and Barne established himself as one of the town's new members, which gave his family the seat until it was abolished in the 1832 Reforms.Born in October 1718, Barne was the only son of Miles Barne, a London merchant and a Director of the East India Company who was the great-grandson of the MP Sir William Barne.His mother was Elizabeth, daughter of Solomon Snowdon, of York.