---
title: "Eighteenth Amendment | Model Diplomat"
description: "The Eighteenth Amendment banned the manufacture, sale, and transportation of intoxicating liquors in the U.S., marking the start of Prohibition in 1920."
url: "https://modeldiplomat.com/learn/glossary/eighteenth"
---

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Model Diplomat Research Team · Last reviewed June 22, 2026

TL;DR

- The Eighteenth Amendment to the U.
- S.
- What is the difference between the Eighteenth Amendment and the Volstead Act?
- How was the Eighteenth Amendment repealed?
- Why is the Eighteenth Amendment constitutionally unusual?

[Civil Service & Diplomatic Exams](https://modeldiplomat.com/learn/civil-services/glossary)Updated June 22, 2026

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## Timeline

1. 18 December 1917

   The Eighteenth Amendment to the United States Constitution, proposed by Congress on and ratified on 16 January 1919, established national Prohibition by ban…

2. 16 January 1919

   The Eighteenth Amendment to the United States Constitution, proposed by Congress on 18 December 1917 and ratified on , established national Prohibition by ba…

3. 17 January 1920

   It took effect one year after ratification, on .

4. 5 December 1933

   The Twenty-First Amendment, ratified , repealed the Eighteenth in full — the only such repeal in American constitutional history — and uniquely was ratified…

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Example

In 1931, federal agents under the Volstead Act enforcing the Eighteenth Amendment secured the conviction of Chicago crime boss Al Capone — though ultimately on tax-evasion charges rather than bootlegging itself.

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