The history of anti-war protests in the United States is as old as the country itself. Every war in American history—even the one that spawned the country—generated internal dissent from pacifists who rejected all wars and from citizens who objected to specific military conflicts on moral, religious, political and economic grounds. The following is a brief timeline of anti-war movements dating back to the birth of the republic.

A significant minority of American colonists supported the British crown during the Revolutionary War. Historian Paul H. Smith estimated that approximately 500,000 colonists were Loyalists, with 19,000 taking up arms against the rebel patriots. Tens of thousands of Loyalists, who tended to be wealthy landowners and businessmen dependent on British trade, fled to Canada and other parts of the British Empire after the revolution.

Many Quakers, whose theology rejected physical violence, refused to participate in the war even though they risked persecution by patriots and Loyalists. Some pacifist Quakers refused to pay taxes that funded militias or use paper money issued by the Second Continental Congress.

READ MORE: 7 Events That Led to the American Revolution

The first war to be declared by the United States sparked one of the strongest anti-war movements in American history. The Federalist Party stronghold of New England, in particular, opposed war with Great Britain on political and economic grounds. New England Federalists viewed the War of 1812 as a partisan crusade launched by Democratic-Republican President James Madison that would disrupt the region’s shipping and fishing industries. Advocating states’ rights, the governors of Massachusetts and Connecticut denied the use of their state militias in service of “Mr. Madison’s War”—with the former even secretly attempting to negotiate a separate peace.

In December 1814, 26 New England Federalist leaders convened in the Connecticut capital and threatened secession. The Hartford Convention’s proposal to amend the U.S. Constitution arrived in Washington, D.C., just after news of the war’s conclusion. The poor timing led to accusations of treason and a backlash that led to the Federalist Party’s eventual collapse.

Protests against the Mexican-American War also centered in New England, but this time based more on morality than economics. Some Americans viewed the war as an act of aggression, rather than self-defense, and thus counter to the country’s values.

Even stronger resistance came from anti-slavery “Conscience Whigs,” such as Massachusetts Senator Charles Sumner, who feared the country’s westward expansion would expand slave-holding territory in the aftermath of the annexation of Texas.

Frederick Douglass denounced the war, and abolitionist William Lloyd Garrison published anti-war letters in The Liberator. The New England Workingmen’s Association opposed the war and vowed to “not take up arms to sustain the Southern slaveholder in robbing one-fifth of our countrymen of their labor.” Author Henry David Thoreau was arrested for refusing to pay taxes that could be used for what he deemed an imperialist war. His subsequent essay “Civil Disobedience,” which advocated following one’s conscience—even if it required breaking the law—became a seminal work in the nonviolent protest movement.

READ MORE: 10 Things You May Not Know About the Mexican-American War

Some in the North opposed the Civil War on economic grounds. They included border states such as Maryland, where slavery was legal, and New York City, where Mayor Fernando Wood considered secession since the city’s commerce and wealth relied so much on Southern cotton. (Inside the Confederacy, opposition centered in Appalachian areas largely devoid of slave-holding plantations.)

Anti-war Democrats in the North, known as “Copperheads,” accused President Abraham Lincoln of acting like a despot and sought an immediate peace. The Copperheads included Democrats repelled by the war’s astounding death toll, those who believed Lincoln violated the U.S. Constitution by suspending certain civil liberties, and those who sympathized with the Confederacy, preferring the restoration of the Union with slavery. Their leader, Ohio Congressman Clement Vallandigham, was arrested for criticizing the war and exiled to the Confederacy in May 1863. The Copperheads found their strongest support in the Midwest and among urban immigrants, particularly after the enactment of the Emancipation Proclamation and a strict new conscription law that allowed wealthy men to pay substitutes to serve in their steads. Growing resentment among working-class Irish Americans in mill cities and mining towns in the Northeast burst into violence in the New York Draft Riots, which left hundreds dead.

READ MORE: How the New York Draft Riots Became the Most Violent Insurrection in American History

With the United States finally emerging from an economic depression following the Panic of 1893, American business leaders feared war with Spain would lead to inflation and threaten the gold standard. “The anti-war class comprises those who are engaged in the creation and distribution of the national wealth—the industrialist, the merchant, the railroad investor,” reported the New York Journal of Commerce in March 1898.

Prominent politicians, academics, authors and businessmen who also had moral concerns about the Spanish-American War formed the Anti-Imperialist League in June 1898 to protest the annexation of the Philippines as a violation of American ideals. Mark Twain, Andrew Carnegie and Grover Cleveland were among the organization’s 500,000 members. The league failed, however, to stop the annexation of the Philippines, which led to a three-year counterinsurgency that claimed tens of thousands of lives.

READ MORE: 6 Things You May Not Know About the Spanish-American War

After war broke out in Europe in 1914, American women played a leading role in subsequent protests. On August 29, 1914, approximately 1,500 women wearing black dresses and black armbands engaged in a funereal march down New York City’s Fifth Avenue. The Women’s Peace Parade was one of the first public anti-war demonstrations in American history.

In January 1915, social reformer Jane Addams was among the organizers of the Woman’s Peace Party, which demanded “that women be given a share in deciding between war and peace in all the courts of high debate.” That spring, Addams chaired the anti-war International Congress of Women in the Netherlands.

Broad-based opposition to American involvement in World War I ranged from industrialist Henry Ford, who sailed to Europe with anti-war activists on his “Peace Ship,” to Socialist Party leader Eugene V. Debs. When the United States entered the war, President Woodrow Wilson cracked down on dissent. Anarchists Emma Goldman and Alexander Berkman as well as Debs were among those jailed after urging resistance to the military draft.

READ MORE: 8 Events That Led to the Outbreak of World War I

As Europe again lurched toward war in the 1930s, American isolationists sought to avoid a repeat of World War I. The America First Committee, which staged mass rallies and broadcast radio advertisements, led the charge. Two future presidents, Gerald Ford and John F. Kennedy, supported the anti-war organization on their college campuses, and aviator Charles Lindbergh and Father Charles Coughlin—who called for American neutrality even if Germany conquered Great Britain—became its most prominent advocates. The right-wing “mothers’ movement,” which saw Nazi Germany as an ally against communism, also urged isolation in anti-war books and pamphlets.

In May 1940, a Gallup poll found that only 7 percent of Americans believed the United States should declare war on Germany. Public opinion started to turn with the fall of France and the Battle of Britain, but the bombing of Pearl Harbor decimated anti-war sentiment. In the week following the Japanese attack, only 7 percent of Americans wanted the country to stay out of war. Representative Jeannette Rankin, who had also voted against American participation in World War I, was the lone vote in Congress against the country’s entry into World War II.

READ MORE: 6 World War II Innovations That Changed Everyday Life

With anti-communism having broad support in the early years of the Cold War, even liberal magazines such as The New Republic and The Nation supported the decision by President Harry Truman to lead an international response to repel the invasion of South Korea by communist North Korea. Opposition to the Korean War was primarily political—particularly against Truman’s decision not to seek a formal declaration of war in deploying troops and his decision to fire General Douglas MacArthur due to disagreements over the war’s conduct.

The largest and most organized anti-war movement in American history arose during the Vietnam War. After the escalation of bombing of North Vietnam, protests questioning the war’s morality sprouted on college campuses in 1965 as faculty and students staged “teach-ins” with anti-war seminars replacing regular classes. The peace movement soon spilled onto American streets with massive demonstrations such as an October 21, 1967 rally at the Lincoln Memorial that drew 100,000 protestors, some of whom then clashed with authorities at the Pentagon.

Protest songs became pervasive in popular culture, and civil rights leaders such as Martin Luther King, Jr., who declared the Vietnam War “a blasphemy against all that America stands for,” supported the anti-war movement. Heavyweight boxing champion Muhammad Ali was the most notable of the “conscientious objectors” who refused to report when drafted.

Following President Richard Nixon’s announcement of the invasion of Cambodia, the Ohio National Guard opened fire on a student protest at Kent State University, killing four and sparking countrywide demonstrations. Some returning from the battlefield joined the protests. An April 1971 rally staged by Vietnam Veterans Against the War culminated with hundreds of veterans hurling their medals and combat ribbons onto the steps of the U.S. Capitol.

READ MORE: How the Vietnam War Draft Spurred the Fight to Lower the Legal Voting Age

There was little protest against the 1991 Persian Gulf War in which the United States led an international coalition to repel the Iraqi invasion of Kuwait, but that was not the case more than a decade later. Although most Americans supported the invasion of Afghanistan following the September 11, 2001, attacks, huge protests questioned the purpose of the 2003 Iraq War that toppled the government of Saddam Hussein.