Forty cars started the inaugural 1911 Indianapolis 500. The field was assembled after 46 cars were entered and 40 successfully qualified under the event’s early speed requirement.
The race was held on May 30, 1911, at Indianapolis Motor Speedway, then a relatively new brick-paved automobile facility. Each car had to demonstrate that it could sustain at least 75 mph over a quarter-mile section. The starting order was based on the date entries were filed, not on qualifying speed, so the grid did not resemble the modern pole-position system.
The 40-car field lined up in rows, generally five cars across, with a pace car included at the front. Ray Harroun won in the Marmon Wasp, averaging 74.602 mph over 500 miles. Only 12 cars were credited with completing the full distance, while the rest retired or were flagged with fewer than 200 laps. The number 40 refers to cars that actually started, not the larger number of entries submitted.