Amendment XVIII (the Eighteenth Amendment) of the United States Constitution, along with the passage of the Volstead Act (which defined "intoxicating liquors"), established Prohibition. The amendment was ratified on January 16, 1919, having been approved by 36 states. It went into effect one year later on January 16, 1920. The amendment was later repealed by the Twenty-First Amendment in 1933.
The text of the Eighteenth Amendment:
Section 1.
After one year from the ratification of this article the manufacture, sale, or transportation of intoxicating liquors within, the importation thereof into, or the exportation thereof from the United States and all territory subject to the jurisdiction thereof for beverage purposes is hereby prohibited.
External link
17th Amendment
Amendments
United States Constitution19th Amendment