Motocross first evolved in the United Kingdom from motorcycle trials competitions, such as the Auto-Cycle Clubs's first quarterly trial in 1906 and the Scottish Six Days Trial that began in 1909.[1][2] When delicate balancing and strict scoring of trials were dispensed with in favour of a race to be the fastest rider to the finish, it was called scrambles, said to have originated in the phrase, "a rare old scramble" describing one such early race.[1] Originally known as scrambles racing in the United Kingdom, as the sport grew in popularity, the competitions became known internationally as motocross racing, by combining the French word for motorcycle, motocyclette, or moto for short, into a portmanteau with "cross country".[1] 

Motocross first evolved in the United Kingdom from motorcycle trials competitions, such as the Auto-Cycle Clubs's first quarterly trial in 1906 and the Scottish Six Days Trial that began in 1909.[1][2] When delicate balancing and strict scoring of trials were dispensed with in favour of a race to be the fastest rider to the finish, it was called scrambles, said to have originated in the phrase, "a rare old scramble" describing one such early race.[1] Originally known as scrambles racing in the United Kingdom, as the sport grew in popularity, the competitions became known internationally as motocross racing, by combining the French word for motorcycle, motocyclette, or moto for short, into a portmanteau with "cross country".[1]  ^{(Wikipedia 44).}

The two competitions that started motocross were the Auto-Cycle Clubs and the Scottish Six Days. Motocross started in the United Kingdom. The whole idea in the beginnings of motocross was to be the first person to finnish in the race, but they weren't called races but rather "scrambles." The word motocross was created by combining the French word Motocross with cross-country (page 1 wikipedia.)

"In 1952, the FIM, motorcycling's international governing body, created an individual European Championship using a 500 cc engine displacement formula.[4]^{" (Wikipedia paragraph 3.)}