'Moto-cross' is a French word, combing 'motorcycle' with 'cross country'. The sport of motocross was popularized in Europe during the 50's & 60's, primarily in Western Europe. Most events were held in open fields and pastures, and the best riders were from Europe. Even today, motocross is run outdoors, on natural terrain tracks. The races are longer (typically close to 40 minutes) and the tracks have higher top speeds.
Motocross came to the United States in the mid-60's, and the idea originated with a man named Edison Dye. He helped bring over the best riders from Europe to help showcase the sport to America. Over the next few years, some of the top riders that came over to America back then included World Champions Torsten Hallman, Bengt Aberg, Joel Robert, and Roger De Coster, along with many other great riders. Roger De Coster is a big reason why motocross became popular in the USA - De Coster really struck a nerve with American fans. His style, professionalism, the winning of 5 World Motocross Championships, and the way he conducted him-self in public and with the media made him a fan favorite. He is still involved in USA motocross today as Team Manager of US Suzuki.
In those early years, the American riders were no match for the Europeans. In most races, it was a feat for an American to even finish in the top ten. But America had fallen in love with motocross. Slowly, they learned training techniques, conditioning, and gained experience both in racing with the Europeans when they came to the USA, and by some Americans going to Europe to compete in the World Motocross Championships. In 1973, Jim Pomeroy became the first American to win a motocross world championship Grand Prix, capturing the opening round in Spain of that year's world championship series. In 1982, Brad Lackey became the first American to win a World Motocross Championship title, riding for Suzuki in the 500cc class. A few weeks later, Danny LaPorte became the second American to win a World Motocross Championship, capturing the 250cc series riding for Yamaha.
The tide had turned, in that American riders were now on par with the Europeans, and, the American Motorcyclist Association (AMA) had nurtured America's National Motocross Series into something prestigious enough that some European riders were coming over to the USA to contest the AMA National Series. Today, they are two primary motocross series being contested in the world – the FIM World Motocross Grand Prix series, consisting of 15 rounds all over the globe, and the AMA National Motocross series, consisting of 12 rounds across the USA.
Text courtesy of : www.supercross.com