The 1924 Grand Prix season saw Grand Prix motor racing spread further across Europe and North America. In Italy a number of new open-road events were held. In France two new circuits were opened – at Montlhéry near Paris and Miramas near Marseille.
After Fiat's dominance the previous year with its supercharged Type 805, most teams adopted supercharging with their new cars. Significantly the French teams of Bugatti, Delage and Rolland Pilain chose not to.
The first major event of the year, at the Targa Florio on Sicily, saw a big German contingent, led by Mercedes, arrive to take on the Italian teams. From the staggered start it became a duel between Christian Werner and Antonio Ascari's Alfa Romeo. But in a repeat of the previous year, his car stopped within sight of the finish line. Pushed by the spectators he was disqualified, giving victory to the Mercedes.
The entry list for this year's Indianapolis 500 was dominated by Millers. They were up against Fred Duesenberg's team with his new supercharged straight-8. Joe Boyer's Duesenberg initially took the lead until supercharger issues forced him to pit. The Millers of Jimmy Murphy and Earl Cooper then traded the lead for most of the race. Boyer meanwhile had swapped cars with his teammate L. L. Corum and gradually reeled in the leaders, taking the lead with 24 laps to go. Boyer and Corum won at a record pace and gave Duesenberg their first Indianapolis victory, also being the first drivers given a shared victory in the race.
The French Grand Prix, this year's European Grand Prix, maintained its pre-eminence with a strong international field. The race was held again in Lyon, which had held the epic 1914 race. Most works teams arrived with new cars including Bugatti with its iconic Type 35 and Alfa Romeo with the P2. After Pietro Bordino initially led, Antonio Ascari took over and dominated the race. The challenges from Sunbeam and Fiat wilted over time. Then with just three laps to go, Ascari slowed and had to pit but was unable to restart. His veteran teammate Giuseppe Campari came through and won, barely a minute ahead of Albert Divo's Delage.
Having been beaten at their own Grand Prix yet again, the French had high hopes of victory at the San Sebastián Grand Prix. Fiat and Alfa Romeo stayed away to prepare for their national GP. But it was Henry Segrave in the Sunbeam who narrowly won from Meo Costantini's Bugatti and André Morel in a Delage.
The dominance of Alfa Romeo dissuaded Bugatti and Delage from the Italian Grand Prix. Injuries to their drivers then caused Fiat to pull out and Mercedes were not ready yet so the organisers postponed the race for six weeks. Only four teams arrived for the race in October which would be a contest between Alfa Romeo and the new Mercedes. But when Louis Zborowski crashed his Mercedes and was killed, the rest of the team was withdrawn. Ascari won, leading a 1-2-3-4 result for Alfa Romeo.
With the increased Interest in the 2-litre formula, voiturette racing fell back into the background predominantly for local and lead-in races. This year the results were shared between the Talbot 70, the Salmson VAL and new arrival Amilcar.