The Alien and Sedition Acts were four bills passed in 1798 by the Federalists in the 5th United States Congress

5th United States Congress

The Fifth United States Congress was a meeting of the legislative branch of the United States federal government, consisting of the United States Senate and the United States House of Representatives...

 in the aftermath of the French Revolution's

French Revolution

The French Revolution , sometimes distinguished as the 'Great French Revolution' , was a period of radical social and political upheaval in France and Europe. The absolute monarchy that had ruled France for centuries collapsed in three years...

 reign of terror

Reign of Terror

The Reign of Terror , also known simply as The Terror , was a period of violence that occurred after the onset of the French Revolution, incited by conflict between rival political factions, the Girondins and the Jacobins, and marked by mass executions of "enemies of...

 and during an undeclared naval war with France, later known as the Quasi-War

Quasi-War

The Quasi-War was an undeclared war fought mostly at sea between the United States and French Republic from 1798 to 1800. In the United States, the conflict was sometimes also referred to as the Franco-American War, the Pirate Wars, or the Half-War.-Background:The Kingdom of France had been a...

. They were signed into law by President John Adams

John Adams

John Adams was an American lawyer, statesman, diplomat and political theorist. A leading champion of independence in 1776, he was the second President of the United States...

. Opposition to Federalists among Democratic-Republicans reached new heights at this time since the Democratic-Republicans had supported France. Some even seemed to want an event similar to the French Revolution to come to the United States to overthrow the Federalists.