Dewar mụrụ na Glasgow, gụrụ akwụkwọ akụkọ ihe mere eme, ma mechaa bụrụ onye ọka iwu na Mahadum Glasgow. Tupu ọ banye na ndọrọndọrọ ọchịchị, ọ rụrụ ọrụ dịka onye ọka iwu na Glasgow. Mgbe ọ dị afọ iri abụọ na asatọ, a họpụtara ya na British House of Commons, na-anọchite anya Aberdeen South site na 1966 ruo 1970. Mgbe ọ tụfuru oche ya, ọ laghachiri n'iwu na ọbụna kwadoro ihe ngosi okwu nke ya n'uhuruchi Fraịde na Radio Clyde. A họpụtara Dewar ọzọ na ntuli aka nke Glasgow Garscadden nke afọ 1978 wee jee ozi dị ka onye omebe iwu ruo mgbe ọ nwụrụ na 2000. Mgbe mmeri ndị Labour meriri na 1997, Onye isi ala Tony Blair họpụtara ya Onye odeakwụkwọ nke Steeti maka Scotland. Dịka onye odeakwụkwọ nke Scotland, ọ bụ onye nkwado nke ikike nke Scotland, ma mee mkpọsa maka ndị omeiwu Scottish na 1997 Scottish referendum referendum
Ọ dị mma. Mgbe emechara mkpọsa nke ọma, Dewar rụrụ ọrụ n'ịmepụta Iwu Scotland 1998.