Motocross was an evolution of the British off-road event called scrambling, which was an evolution of motorcycle trial events popular in the northern UK. The first known scramble took place at Camberley, Surrey in 1924.^[1] During the 1930s, the sport grew in popularity, especially in Britain where teams from the Birmingham Small Arms Company (BSA), Norton, Matchless, Rudge, and AJS competed in the events. Off-road bikes from that era differed little from those used on the street. The intense competition over rugged terrain led to technical improvements in motorcycles. Rigid frames gave way to suspensions by the early 1930s, and swinging fork rear suspension appeared by the early 1950s, several years before it was incorporated on the majority of production street bikes.^[2] The period after the Second World War was dominated by BSA which had become the largest motorcycle company in the world.^[2] BSA riders dominated international competitions throughout the 1940s.^[2]

In 1952 the FIM, motorcycling's international governing body, created an individual European Championship using a 500 cc engine displacement formula. In 1957, it was upgraded it to World Championship status.^[2] In 1962, a 250 cc world championship was created.^[2] It was in the smaller 250 cc category that companies with two-stroke motorcycles came into their own. Companies such as Husqvarna from Sweden, CZ from the former Czechoslovakia and Greeves from England, became popular due to their lightness and agility.^[2] By the 1960s, advancements in two-stroke engine technology meant that the heavier, four-stroke machines were relegated to niche competitions. Riders from Belgium and Sweden began to dominate the sport during this period.^{[citation needed]}