After WWI, Opel updated its Rüsselsheim factory to accommodate a Ford-type moving assembly line, ditching its existing range of models to concentrate on just one, which was a blatant copy of the successful Citroën 5CV.

Known as the Laubfrosch (treefrog) because of its green livery, this new light car first appeared in the spring of 1924, setting Opel on a road to success that would see it established as Germany's largest auto maker by the end of the decade.

By 1936 the Laubfrosch had metamorphosed into the perpendicular-styled P4, which in turn was superseded by the Kadett, a unitary construction model that showed the unmistakable influence of Opel's new owners, General Motors.

Mechanically almost identical to the P4, the Kadett was powered by a 1,074cc sidevalve four and in Standard guise featured beam axles and hydraulic brakes while the more expensive Master version came with independent front suspension.

Named in commemoration of the 1936 Olympic Games in Berlin, this right-han...