The movement for the prohibition of alcohol began in the early 19th century, when Americans concerned about the adverse effects of drinking began forming temperance societies. By the late 19th century, several states and dozens of cities had enacted prohibition laws, and temperance groups had become a powerful political force, campaigning on the state level and calling for total national abstinence. In December 1917, Congress passed the 18th Amendment, commonly known as the Prohibition Amendment. It took effect in January 1919, following state ratification.
Despite an often-vigorous effort by law-enforcement agencies, the federal government failed to prevent the large-scale distribution of alcoholic beverages, and organized crime flourished in America during the 1920s. In 1933, the 21st Amendment to the Constitution was passed and ratified, repealing Prohibition.