Born in Lodi, not far from Milan, Castellotti came a family of means. He bought a Ferrari sportscar in 1950 when he was still only 20 years of age and he campaigned it enthusiastically in Italian events in 1951 and 1952.

In the second year he began winning, taking victory in the Sicily Gold Cup, the Circuito di Senigallia and the sportscar Portuguese GP. He also finished second in the Monaco GP, run that year for sportscars. But he really hit the headlines when he ran second in the Mille Miglia, this led to him being offered a drive with the Lancia sports car team for the 1953 Carrera Panamericana. He finished third behind Juan Manuel Fangio and Piero Taruffi. he also won the Italian hillclimb championship and the 10 Hours of Messina.

The Lancia connection resulted in him being signed by the Turin company for its Formula 1 programme in 1954. The cars were late arriving and Castellotti did not get to race one of the D50s until the start of 1955. At Pau he finished second ahead of his team mates Gigi Villoresi and Alberto Ascari (although the latter had mechanical trouble). He also finished second at Monaco. A few days later Ascari was killed testing a Ferrari sportscar and with Villoresi talking of retirement, Castellotti became team leader for one Grand Prix. Then Lancia closed its racing programme and the D50s were sold to Enzo Ferrari. Castellotti thus became a Ferrari driver but there were too many drivers on the books and so Eugenio concentrated on on sports cars, winning the Mille Miglia driving half the race in the pouring rain with no visor, and the Sebring 12 Hours. In F1 the high point of his year was second place to Peter Collins in the French Grand Prix at Reims, while he spun out of the race at Monza with tyre failure after an indisciplined battle with team-mate Luigi Musso.

In the early months of 1957 Castellotti featured more in the gossip columns than the motoring magazines due to his high profile affair with opera singer Delia Scala. While on holiday in Florence, he was annoyed to be summoned back to Modena by Enzo Ferrari to do something about the new unofficial lap record which had just been set by Jean Behra in the latest Maserati 250F at the Modena Autodrome. On only his third lap, Castellotti crashed into a small grandstand and was killed instantly.

Four years later, another italian driver, Giulio Cabianca, Castellotti's best friend, died at the same track.

Major career wins (sportscars):

• Mille Miglia
• 12 Hours of Sebring
• Sicily Gold Cup
• Circuito di Senigallia
• Portuguese Grand Prix