Alfa Romeo began participating in Formula 1 in 1950, both as a constructor and engine supplier, with immediate success. Driving a 158 with supercharger, Nino Farina stormed to World Championship glory in the inaugural season in 1950. More success followed in 1951 when Juan Manuel Fangio claimed the 1951 title, this time in an Alfetta 159.

Despite the instant success of the Alfa cars, a lack of government funding left the company unable to compete with the technology of companies such as Ferrari, and so rather than compromise their winning streak the company withdrew from Formula 1.

Throughout the 1960s, Alfa Romeo engines were used by several smaller racing teams – initially straight-4 engines. Towards the end of the decade a V8 engine was developed and Alfa made a brief return to racing – it was however an unsuccessful one as the cars often failed to qualify, and were not competing for podiums when they did.

Alfa Romeo made a full return to the sport in 1979 and continued to race up until 1985, with the company’s final race to date coming at the 1985 Australian Grand Prix..

Source:Wikipedia (is it ever anywhere else??)