Sir Oswald Moseley, BUF Leader
An Anglo-Irish aristocrat, Mosley fought on the Western Front and was later elected to Parliament as the Conservative MP for Harrow on an anti-war policy. He jumped ship to Labour over the use of the infamous Black and Tans in Ireland, then joined the ILP and became a prominent Fabian, eventually starting a new left-wing party which failed in 1931.
He made another abrupt turn and joined the fascists, initially modelled upon Mussolini's party but then increasingly the Nazis, which rapidly lost him mass support. Mosely was dangerously charismatic. Adolf Hitler apparently had plans for Mosely had Britain fallen noting rather sinisterly that, (Mosely) could never become a real leader like himself (but) his role is not over yet.
1 Metal Oswald Mosely with 2 metal bodyguards