In 2015, cars manufactured in 1990 that didn’t pass safety or emissions regulations the first time around became legal to import to the U.S., and among that impressive class — which included the Lotus Carlton, Volkswagen Golf Country, and Alpina B10 Bi-Turbo — stood the Mazda Eunos Cosmo, one of the greatest “what-if” cars of all-time. In Japan, the Cosmo’s nameplate had an incredible three-decade run as one of the most innovative grand tourers of its era, and even though we never got it the first time around, it had a profound effect on shaping the Mazda, something that can still be felt today.

Founded in 1920, Toyo Kogyo Co., Ltd. was founded in Hiroshima and came to prominence 11 years later when it introduced the Mazda-Go three-wheeled motorcycle. During World War II, the company produced rifles for the Japanese military, and after rebuilding in the early post-war years, it went back to building three-wheeled motorcycles and small trucks. In 1960, it introduced its first car, the R360, one of the most popular kei-cars of the era. But Mazda could see that there was a world out there larger than selling small cars on the home islands, and sought to expand.

In the early 1960s, the engine of the future looked to be the Wankel rotary engine, a smooth, free-revving engine with fewer moving parts than a standard internal combustion unit. In 1964, German company NSU had developed a commercially viable single-rotor rotary engine and introduced it in its compact rear-engined Spider. That year, Mazda sensed that rotary-power would be the next great automotive development, and entered a partnership with the automaker to further develop its technology.

Just months later, Mazda unveiled the 110S Cosmo at the Tokyo Motor Show: the world’s first true rotary-powered sports car. 

Between 1964 and ’67, Mazda built 80 110Ses for pre-production and dealership testing, making sure to work out many of the new engine’s problems. Partner NSU wasn’t so lucky; its rubber apex seals were no match for the high heat of the engine, leading to a shockingly high number of engine failures before 100,000 miles. Mazda didn’t have that problem; with its carbon seals and bi-rotor setup, the Cosmo turned out to be a capable little sports car. Its 110 horsepower and 96 pound-feet of torque were minuscule compared to what was coming out of Detroit at the time, but with its incredibly low center of gravity and 2,200 pound curb weight, it was an incredibly lively and tossable sports car.

In 1968, after just 343 production cars had been built, Mazda introduced the Series II Cosmo. With 15 inches added to its wheelbase and power bumped to 128 horsepower and 103 pound-feet, it became an even more capable sports car, and was sold against Toyota’s 2000GT in Japan. Mazda even took the Cosmo racing, competing two of them at the 84-hour Marathon de la Route at the Nürburgring in Germany. One car retired with axle trouble after 82 hours; the other came in fourth place.

While the 2000GT was a combination of beautiful style elements collected from around the world, the original Cosmo stands out today for its uniquely Japanese looks. Incredibly small and jewel-like in person, the Cosmo would’ve looked completely alien anywhere outside of Japan in the 1960s. And with its hull-like body and upright greenhouse, it was strange even by Japanese standards. Just over 1,600 Cosmos were built (including the ’63-’66 prototypes) between 1967 and 1972, and while they weren’t widely available in the U.S. (Mazda did bring around five of them to the U.S. to gauge dealer interest), their technology was instrumental in establishing the brand stateside, and setting its agenda for decades to come.

In the pre-Gas Crisis 1970s, Mazda quickly became one of the most popular Japanese brands in the U.S. Much like today, its reputation for sporty, well-built and affordable cars set it apart from some of the more staid offerings from Toyota and Datsun. But unlike its competitors, it was the only game in town when it came to rotary power — so much so that it emblazoned “ROTARY POWER” across the tailgate of its Rotary Pickup model.

Thanks to cars like the Chevy Monte Carlo and Lincoln Mark III, the Personal Luxury Coupe segment was fast becoming one of the most popular segments in the U.S., and Mazda was eager to get into the game — and finally bring the Cosmo to America. Introduced in 1975, the second-generation car was less of a Japanese GT and more of an Eastern take on the Pontiac Grand Prix, right down to the available vinyl roof and opera windows. It was available with Mazda’s new 12A bi-rotary engine, which had become the first Japanese-built engine to finish a 24 Hours of Le Mans, in 1974. The Japanese market loved the new Cosmo’s American-influenced styling, snapping up over 55,000 cars in the first year alone. In contrast, the Cosmo was pulled from American dealers in 1978 after abysmal sales. It would never again be available stateside.

The Cosmo was replaced in the U.S. with the RX-7, a rotary-powered sports car that had far more in common with the original Cosmo than the second-generation car did. And while the RX-7 proved to be one of the first international sales successes for the brand, the Cosmo nameplate soldiered on. A high-tech luxury grand tourer bowed for 1981 based on the luxury 929 flagship. With pop-up headlights, a digital dash, and wedge-shaped styling, the third-generation could be available with a turbocharged 12A engine, making it the fastest car in Japan until the Nissan R30 Skyline RS debuted in 1983.

In the 1980s, the Japanese economy experienced unparalleled growth, and as a result, the automotive industry was flush with cash. Mazda sank its share into a number of complex new models, and a number of sub-brands. Once again, the Cosmo was to be its international Flagship. Toyota, Honda, and Nissan had all recently established luxury brands to take on the Americans and Europeans, and Mazda was looking to get in on the action. The new Cosmo was launched under the Eunos brand in 1989. It would be launched under the all-new Amati brand in the U.S. in 1993.

But it wasn’t to be; The Japanese economic bubble burst, and Mazda was forced to scuttle its plans. What was left was a JDM-only grand tourer unlike anything the brand had ever built before. The fourth-generation Cosmo’s closest rivals were the Lexus SC400 and Jaguar XJS. Starting at roughly $27,000 and topping out at over $43,000, the Cosmo wasn’t cheap, but in top spec, its performance was more in line with the V12-powered (and much more expensive) Mercedes SL500 and BMW 850i, making it a bargain.

By the ’90s, Mazda was the only game in town when it came to rotary engines, and it had come a long way. At a time when its hottest RX-7 model came with a twin-turbo bi-rotor engine, the Cosmo was available with a twin-turbo tri-rotor engine, the largest automotive one Mazda had ever built. Pumping out up to 320 horsepower and 297 pound-feet of torque in top trim, the engine could spin to 9,000 RPM, but redline was pegged at 7,000 because the transmission couldn’t handle it. Inside, the car was a technological showcase: With a wrap-around Lexus-like backlit instrument panel, the Cosmo also had GPS, a mobile phone, and its stereo and HVAC systems were controlled by a touchscreen — a marvel in 1989.

The Cosmo soldiered on until 1995, when Mazda announced it would be discontinued after the ’96 model year. Just 8,853 final-generation cars had been built, with the bulk of them sold in its first few years. Today, first and last-generation Cosmos are becoming desirable collector cars, with ’67 to ’73 models changing hands for six-figure sums, and well-kept ’90s-era cars fetching upwards of $30K around the world.

Had an Amati Cosmo come to the U.S. 23 years ago its price likely would have kept it from becoming a success, and it’s not hard to envision it being trounced by the comparatively tame Lexus SC300 in the sales department. Still, the Cosmo (with maybe the exception of the second-generation car) always seemed to be ahead of the curve, maybe even more than American car buyers could’ve realized at the time. With the benefit of hindsight, collectors are beginning to realize that they were some of the most exciting cars to ever come from Japan. And with Mazda’s recent RX-Vision concept, and announcement that it’s working on rotary engines again, the Cosmo name could live on in the 21st century. We hope that it does; this time, we’ll be ready for it.

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