The American Automobile Association Contest Board first sanctioned automobile motorsport events in 1902, initially applying the rules of the Automobile Club of America before forming its own regulations in 1903. The first formal track season championship was introduced in 1905, with Barney Oldfield recognized as the inaugural champion. No official championship was contested between 1906 and 1915, though racing continued. The 1916 season is regarded as the next official championship campaign. Racing was suspended during both World Wars — the Indianapolis 500 was voluntarily halted in 1917 and 1918, and all U.S. automobile racing was banned by government order from 1942 to 1945 due to wartime rationing.
Through 1922 and again between 1930 and 1937, it was common for the cars to carry a riding mechanic alongside the driver, making them two-seaters rather than the standard single-seat configuration. The AAA withdrew from motorsport sanctioning at the end of 1955, citing a series of high-profile fatal accidents including the death of Bill Vukovich during the 1955 Indianapolis 500 and the 1955 Le Mans disaster.
The United States Auto Club, formed by Indianapolis Motor Speedway owner Tony Hulman, assumed the national championship in 1956. During the 1950s, front-engined roadsters dominated paved oval tracks while upright Champ Dirt Cars ruled on dirt. Through the 1960s, teams and drivers with road racing backgrounds — both American and foreign — drove a rapid transition to rear-engined, formula-style machines. Technology, speeds, and costs climbed sharply. Dirt track rounds were dropped from the national championship after 1970.
By the late 1970s, rising costs and dissatisfaction with USAC management prompted leading team owners — among them Penske, Patrick, Gurney, and McLaren — to consider an alternative. The death of Tony Hulman in the fall of 1977 and a plane crash that killed eight key USAC officials shortly after accelerated the break. By the end of 1978, the major owners had founded Championship Auto Racing Teams to wrest control of the national championship from USAC.
CART was formed by most existing team owners with initial assistance from the SCCA. USAC ran a parallel 1979 season with few prominent names — A.J. Foyt being the main exception — while CART quickly became the more prestigious championship. At the 1979 Indianapolis 500, USAC denied entries from several CART-affiliated teams; a court injunction during the month of May ultimately allowed them to participate. An attempt to reconcile the two bodies under a joint Championship Racing League structure in 1980 collapsed when USAC withdrew. Johnny Rutherford won both the USAC and CART championships that year.
Stability returned as CART ran the national championship full-time, with the Indianapolis 500 remaining under USAC sanction but counting toward CART points. The racing was highly competitive, attracting international drivers and generating substantial television and sponsor interest. Speeds on superspeedways reached and exceeded 200 miles per hour. The series attracted broad international participation and was considered among the world's premier open-wheel categories through this period.
In 1994, Tony George — Tony Hulman's grandson and president of the Indianapolis Motor Speedway — announced the formation of the Indy Racing League to begin competition in 1996. The IRL placed the Indianapolis 500 at its center and offered automatic qualifying slots to teams that competed in IRL rounds, effectively preventing most CART teams from securing places. CART teams boycotted the 1996 Indianapolis 500 in response. A legal dispute over the "IndyCar" trademark resulted in CART surrendering use of the name.
CART, rebranded as the Champ Car World Series, retained top drivers, teams, and sponsors for several years but steadily lost ground. Major manufacturers and title sponsors switched allegiance to the IRL. CART filed for bankruptcy in 2003; its assets were purchased and the series continued as the Champ Car World Series until 2007, when Bridgestone and Ford withdrew as presenting sponsors. In 2007, Champ Car raced entirely on road and street circuits — the only season in the combined history of major American open-wheel racing without any oval rounds.
Prior to the 2008 season, the Champ Car World Series Board authorized bankruptcy and the series was absorbed into the IRL, reunifying American open-wheel racing for the first time since 1978. The combined series competed as the IndyCar Series. Randy Bernard became IRL chief executive in 2010, the same year the IRL rebranded as IndyCar. The Dallara DW12 chassis was introduced for 2012. The series ran under a succession of title sponsor names — IZOD, Verizon, NTT — before being acquired in 2020 by Penske Entertainment Corp., a subsidiary of Roger Penske's Penske Corporation, which also purchased the Indianapolis Motor Speedway.
The Indianapolis 500, held at the Indianapolis Motor Speedway during Memorial Day weekend, is the most storied event on the calendar and has defined the category's identity for over a century. For much of its history, performances at Indianapolis set the benchmark for open-wheel technology and speed. The race's status within the points championship fluctuated during the various sanctioning body splits but has been a counting round of the IndyCar Series in the unified era.
Indy cars are single-seat, open-cockpit, open-wheel purpose-built racing cars. They share a general lineage with Formula One machinery but are generally larger and configured specifically for the mix of oval and road course racing the series demands. High oval speeds — exceeding 230 miles per hour in qualifying trim at superspeedways — place aerodynamic and structural demands distinct from pure road racing. International races have been held in Canada, Mexico, Brazil, Japan, and Australia, as well as Europe, though the series remains predominantly North American in its schedule.
Gallery · 3 related images
