The Imola circuit traces its origins to 1950, when a road linking existing public routes was constructed through a region already home to racing manufacturers including Ferrari, Lamborghini, Maserati, and Minardi (later Toro Rosso, AlphaTauri, and Racing Bulls). The first motorcycle races took place in April 1953, followed by car racing in June 1954. Formula One cars first appeared at Imola in April 1963 in a non-championship event won by Jim Clark.
In 1980, with Monza under refurbishment following the 1978 accident that killed Ronnie Peterson, the Italian Grand Prix moved to Imola for one year. Nelson Piquet won that race in a Brabham-Ford. When the Italian GP returned to Monza in 1981, Imola's promoters sought a route to remain on the calendar and persuaded the Automobile Club of San Marino to apply for their own Grand Prix. The application succeeded, and the San Marino Grand Prix debuted on the 1981 calendar.
The San Marino Grand Prix quickly developed a reputation for high drama. The 1982 race was boycotted by most FOCA-aligned teams during the FISA–FOCA war, reducing the field to 14 cars. Ferrari's Gilles Villeneuve and Didier Pironi ran the entire race together; despite team orders to hold positions, Pironi passed Villeneuve on the final lap to take the win. Villeneuve, furious at what he saw as a betrayal of trust, declared he would never speak to Pironi again. He died during qualifying for the Belgian Grand Prix two weeks later.
The 1989 race produced one of Formula One's most defining confrontations. Following a restart after Gerhard Berger's fiery accident at Tamburello, McLaren teammates Ayrton Senna and Alain Prost had agreed that whoever reached Tosa first would lead unchallenged. Prost led through Tamburello; Senna drew alongside at Villeneuve and passed into Tosa. Prost disputed the breach of agreement; Senna won, and the incident deepened their already intense rivalry.
Alain Prost won the San Marino Grand Prix five times, the most of any driver. Michael Schumacher matched and ultimately surpassed that total, winning seven times. Ayrton Senna and Prost each won it three times before 1994.
The 1994 San Marino Grand Prix became the darkest weekend in the modern history of Formula One. During Friday practice, Rubens Barrichello suffered a severe concussion in a crash at the Variante Bassa chicane. The following day in qualifying, Simtek driver Roland Ratzenberger crashed at the Villeneuve Corner after his front wing broke, and was killed — the first driver fatality at a Grand Prix since 1982. At the start of the race, a collision between Benetton's JJ Lehto and Lotus's Pedro Lamy sent debris into the crowd, injuring eight spectators.
On lap 7, Williams driver Ayrton Senna — three-time World Champion and widely regarded as the sport's greatest talent — ran off course at the flat-out Tamburello left-hander at approximately 325 km/h, decelerating to around 225 km/h before striking the concrete wall. A fragment of suspension and the right front wheel struck Senna's helmet at high velocity, inflicting fatal head injuries. He was 34 years old.
Michael Schumacher was declared the race winner, but celebrations were entirely absent from the podium ceremony.
The consequences were immediate and far-reaching. Tamburello was redesigned as a chicane before the next race; the Villeneuve corner was similarly altered. The FIA introduced extensive regulation changes across the 1994 and 1995 seasons — covering car dimensions, aerodynamics, and safety cell requirements — and undertook circuit safety reviews across the entire calendar. The 1994 San Marino Grand Prix is widely credited as the event that accelerated the modernisation of Formula One safety infrastructure.
From 1995 to 2006 the race continued without further fatalities. Michael Schumacher won in 1999, 2000, 2002, 2003, 2004, and 2006. Damon Hill won in 1995 and 1996. Fernando Alonso won in 2005. The 2006 race was notable for an accident caused by Japanese driver Yuji Ide which flipped the car of Christijan Albers, leading to the revocation of Ide's FIA superlicense. On 29 August 2006 the race was formally dropped from the 2007 calendar to make room for the returning Belgian Grand Prix, and it has not been held under the San Marino name since.
Imola returned to the Formula One calendar in 2020 as the Emilia Romagna Grand Prix, a name rooted in the Italian region rather than the adjacent microstate.
The San Marino Grand Prix exists as one of Formula One's most historically weighted events. Its 26 editions spanned the turbo era, the manufacturer wars of the late 1980s, and the early years of the Schumacher dynasty. The weekend of 1994 remains the single most consequential in the sport's modern history in terms of its effect on safety regulation, circuit design standards, and the trajectory of Formula One's public image. Williams, Ferrari, and McLaren each won the race multiple times, reflecting the shifting balance of power across the sport's most competitive decades.