The 1975 Spanish Grand Prix, held at Montjuïc circuit was won by Jochen Mass in a McLaren. This was one of the most controversial and tragic race weekends in Formula One history.
The race weekend started with the drivers who were members of the Grand Prix Drivers Association going on strike as they felt that the safety barriers were not bolted together properly. Despite the efforts of the track staff the situation was not resolved by the time qualifying began.
Threatened with legal action the drivers were forced to call off the strike. Emmerson Fittipaldi refused to race and returned home.
Niki Lauda and Regazzoni were on the front row in their Ferraris, but at the start, Vittorio Brambilla hit Mario Andretti who in turn went into the back of Lauda who collected Regazzoni. Lauda retired while Regazzoni limped back to the pits for repairs.
Also on the first lap Patrick Depailler retired with suspension damage while both Wilson Fittipaldi and Arturo Merzario pulled into the pits in protest.
When the smoke had cleared, James Hunt was leading. Andretti, who had managed to keep going, was second, John Watson was third followed by Rolf Stommelen, Brambilla and Carlos Pace.
Jody Scheckter's Tyrrell blew up on lap four depositing oil on the track causing Alan Jones and Mark Donohue to crash and, three laps later, Hunt did the same thing.
Andretti was now leading from Watson and Stommelen. Andretti's rear suspension finally gave up on lap 16 causing him to crash and Watson's Surtees was suffering from severe vibration and he dropped back.
Stommelen was now leading followed by Pace, Ronnie Peterson, Jochen Mass, and Ickx. On lap 24, Peterson was lapping François Migault when they had a coming together putting Peterson out of the race.
Then on lap 25 tragedy struck. The rear wing on Stommelen's Embassy Hill-Lola came off sending him into the barriers. The car rebounded back across the track and vaulted the barrier killing a fireman, a photographer and two spectators. Pace crashed trying to avoid Stommelen, who ended up with a broken leg.
Four laps the race was stopped. Mass had passed Ickx for the lead and was thus declared the winner. Ickx was second and Carlos Reutemann third. Lella Lombardi became the first woman to score points in a World Championship race though as only half points were awarded, she actually only got half of one.