Explores why Dafydd Elis-Thomas, the leader of Plaid Cymru, the Welsh Nationalist party, didn’t believe in nationalism and how this changed Welsh politics. Lord Dafydd Elis-Thomas of Nant Conwy is one of the most outstanding Welsh public figures of the last fifty years. His political career spans from his first election as MP for the Welsh Nationalist Party in 1974 at the age of 27, to May 2021 when he finally retired after twenty-years of service as a member of the Senedd.  At different stages in his career, he was branded a maverick, an intellectual acrobat and political chameleon, a terrorist for his interventions in Northern Ireland, and a traitor for opposing nationalism. As the first Presiding Officer of the National Assembly for Wales he helped stabilize the new institution and embedded devolution in its first tentative decade. His career has often been marked by controversy. This is what makes his story remarkable, just as his political life has proved to be unpredictable. Both controversial and magnetic, the life and thought of Elis-Thomas is captured in this biography.