The automobile was important to the history of the Roaring ‘20s for at least two reasons. One of these reasons was economic while the other had to do with culture and society.
Economically, the rise of the automobile helped to drive economic growth in the 1920s. This was partly because of how many cars were being made. There were over 3 million cars made each year for most of the decade. Each car, of course, had to be made by a number of workers using many different materials. The making of the automobiles and the things like rubber, glass, and steel that went into them provided large numbers of jobs during the decade. In addition, the automobile boom produced jobs in other related areas. There were people who worked to build roads. There were people who worked at gas stations, repair shops, and motels. These, too, were important sources of jobs, making the automobile an important factor in the economy of the 1920s.
While automobiles were economically important, they were also important because they helped change American society. Since so many Americans owned cars, they now had a new source of entertainment. They could enjoy driving in their cars and they could drive to various new places where they could engage in recreation. The cars also gave them a new sense of freedom. Now, they could go (or so they would have felt) anywhere they wanted to go. Young people had a new way to get away from the eyes of their parents. They could drive off and find privacy, perhaps giving them a chance to engage in some degree of physical intimacy. In these ways, cars allowed people more ways to feel free and to engage in leisure activities. This is important to the history of the 1920s because greater freedom and leisure are seen as major characteristics of the decade.