fatal accidents were common
first Mille Miglia
inaugural Monaco Grand Prix
safety standards were minimal
political influence from Nazi Germany and Fascist Italy
gptkb:Nürburgring gptkb:Monaco gptkb:Monza gptkb:Spa-Francorchamps
increased government involvement in motorsport
internationalization of racing calendar
introduction of supercharged engines
professionalization of drivers
rise of German Silver Arrows
technological innovation in aerodynamics