The streets belonged to pedestrians in the United States until mass production of the automobile changed everything at the beginning of the 20th century. In response, two men -- William Phelps Eno in New York and Miller McClintock in Los Angeles -- published books on traffic that together established a blueprint for the country's traffic laws. While Eno's 1903 book paved the way, McClintock's 1925 "Street Traffic Control" became the national model for municipal traffic codes.
License and Registration, Please
As the automobile industry picked up momentum, states and cities enacted traffic laws and put up traffic control devices. Cleveland installed the world's first electric traffic signal in 1914, and Buffalo, N.Y. erected the first "No Left Turn" sign in 1916. Connecticut passed the first speed limit law in 1901, but up to a dozen states had no speed limit laws as late as 1930. Adoption of traffic regulation was slow across the country, and only 39 states required driver's licenses by 1935.
Role of Federal Government
Traffic regulation did not become a national issue until 1966, when Congress passed legislation that put the federal government in charge of safety standards for cars and highways. The cities and states have remained in charge of enacting and enforcing local traffic laws. However, the federal government has put pressure on the states to influence traffic regulations, such as speed limits and impaired driving laws, by conditioning highway funds on the adoption of certain minimum standards.