Gwynfor Evans

Evans won Plaid Cymru's first parliamentary seat at the Carmarthen by-election of 1966, which, like Hamilton in Scotland, pushed Labour towards devolution. His most direct impact came in 1980, when he threatened to fast to death unless the Thatcher government kept its promise of a Welsh-language television channel; the government gave way and S4C launched in 1982. It remains one of the clearest cases of a single politician changing a government decision by personal pressure.