After studying at Christ Church College, Oxford University, he travelled across Europe and realising the strength in diversity amongst people grew to believe that Wessex would be better off as a devolved region within the United Kingdom. He stood in the February 1974 General Election as a Wessex Regionalist and a short time after the election helped form the Wessex Regionalist Party. He stood for the party in the first ever elections to the European Parliament in 1979.
Thynne has written several novels and later sat in the House of Lords after inheriting his father's title. Amongst other things he spoke on the need for devolution for the regions of England, until he lost his place in the House of Lords after the Labour government's reforms excluded most of the hereditary peers.