There have been numerous incidents of political violence in Washington, D.C., the capital of the United States, as well as in the greater Washington Metropolitan area.

19th century

August 24, 1814: Burning of Washington: British forces led by George Cockburn invaded and occupied Washington during the Chesapeake campaign of the War of 1812, after defeating an American force at Bladensburg. In retaliation for acts of destruction by American troops in the Canadas, Cockburn's forces burnt several government buildings in the city, including the White House and the United States Capitol. The occupation only lasted for approximately 26 hours as a storm led to the British abandoning the city. To this date, it remains the only time since the American Revolutionary War that a foreign power has captured and occupied the capital of the United States. April 13, 1832: Sam Houston confronted Representative William Stanbery (OH-08) in Washington, D.C. and beat him repeatedly with a hickory walking stick after Stanbery accused him of profiteering off Andrew Jackson's forced relocation of Native Americans. During the fight Stanbery pulled a gun, placed it on Houston's chest, and pulled the trigger, but the gun misfired. Houston was arrested and charged with breaching the privileges of the House by assaulting Stanbery for remarks made from the floor. January 30, 1835: Just outside the U.S. Capitol, house painter Richard Lawrence aimed two flintlock pistols at President Andrew Jackson, but both misfired: one of them while Lawrence stood within of Jackson, and the other at point-blank range. Lawrence was apprehended after Jackson beat him down with a cane. At trial, Lawrence was found not guilty by reason of insanity and spent the remainder of his life in insane asylums. June 20, 1854: A fight between Representatives William M. Churchwell (TN-02) and William Cullom (TN-04) erupted on the floor of the U.S. House of Representatives. The difficulty between the two began a month earlier during a debate of the pro-slavery Kansas–Nebraska Act. Churchwell accused Cullom and Senator John Bell (TN) of defending the Missouri Compromise of 1820. The confrontation led to a resolution permitting the House to expel a representative who brings a concealed weapon into the chamber.

May 22, 1856: Caning of Charles Sumner: Abolitionist Senator Charles Sumner (MA) was savagely beaten with a cane and nearly killed by pro-slavery Representative Preston Brooks (SC-04) on the floor of the U.S. Senate in retaliation for a speech criticizing slavery. It has been considered symbolic of the "breakdown of reasoned discourse" and the use of violence that eventually led to the American Civil War. February 5, 1858: During the 35th United States Congress, on February 5, 1858, Galusha A. Grow (PA) was physically attacked by Democrat Laurence M. Keitt (SC) in the House chambers, leading to a brawl between northerners and southerners. Keitt, offended by Grow's having stepped over to his side of the House chamber, dismissively demanded that Grow sit down, calling him a "black Republican puppy". Grow responded by telling Keitt that "No negro-driver shall crack his whip over me." Keitt became enraged and went for Grow's throat, shouting that he would "choke [him] for that". A large brawl involving approximately fifty representatives erupted on the House floor, ending only when a missed punch from Rep. Cadwallader Washburn (WI) upended the hairpiece of Rep. William Barksdale (MS). The embarrassed Barksdale accidentally replaced the wig backwards, causing both sides to erupt in spontaneous laughter. April 14, 1865: Assassination of Abraham Lincoln: President Abraham Lincoln was assassinated by John Wilkes Booth while attending the play Our American Cousin at Ford's Theatre. Shot in the head as he watched the play, Lincoln died the following day at 7:22a.m. in the Petersen House opposite the theater. He was the first U.S. president to be assassinated, with his funeral and burial marking an extended period of national mourning. Occurring near the end of the American Civil War, the assassination was part of a larger conspiracy intended by Booth to revive the Confederate cause by eliminating the three most important officials of the U.S. government: the president, the vice president, and the secretary of state. After a dramatic initial escape, Booth was killed at the climax of a 12-day manhunt. His accomplices, Lewis Powell, David Herold, George Atzerodt and Mary Surratt, were later hanged for their roles in the conspiracy. June 14, 1866: A debate between Representative Josiah Grinnell (IA) and Representative Lovell Rousseau (KY) over a bill intended to increase the power of the Freedmen's Bureau devolves into both men insulting each other. Rousseau would insult the state of Iowa while Grinnell would insult the state of Kentucky alongside questioning Rousseau's military record. On June 14th Rosseau would approach Grinnell on the east portico of the US Capitol building and requested an apology. When Grinnell refused to do so he would be struck several times by Rousseau's cane. In response Rosseau would be censured by the House of Representatives. July 2, 1881: Assassination of James A. Garfield: President James A. Garfield was assassinated at 9:30a.m. while he waited for a train at Washington's Baltimore and Potomac Railroad station on the National Mall (at the present location of the National Gallery of Art), less than four months after he took office. As the president was arriving at the train station, writer and lawyer Charles J. Guiteau shot him twice; one bullet grazed the president's shoulder, and the other pierced his back. Garfield lingered for eleven weeks before dying on September 19, 1881, at 10:35p.m. of complications caused by infections, which were contracted by the doctors' relentless probing of his wound with unsterilized fingers and instruments. Guiteau was immediately arrested. After a highly publicized trial lasting from November 14, 1881, to January 25, 1882, he was found guilty and sentenced to death, which took place on June 30, 1882. Guiteau was assessed during his trial as mentally unbalanced, possibly due to the effects of syphilis on the brain. He claimed to have shot Garfield out of disappointment at being passed over for appointment as Ambassador to France.

20th century March 3, 1913: Woman Suffrage Procession: Between 5,000 and 10,000 people marched through Washington, D. C. in support of the women's suffrage movement. Organized by Alice Paul and Lucy Burns and sponsored by the National American Woman Suffrage Association, it turned violent when onlookers attacked the suffragists. July 2, 1915: A few minutes before midnight, the U.S. Senate reception room was bombed by Eric Muenter ( Frank Holt), a German professor who wanted to stop American support of the Allies during World War I, attempting to kill vice president Thomas Marshall among others. The next morning he tried to assassinate J. P. Morgan Jr., son of the financier, at his home on Long Island, New York.

April 2, 1917: When a delegation of pacifists visited the U.S. Senate to oppose American entry into World War I, Senator Henry Cabot Lodge, the leading supporter of the war in the Senate, and pacifist Alexander Bannwart got into a fistfight in the corridors of the U.S. Senate. June 2, 1919: Attempted assassination of A. Mitchell Palmer during the 1919 United States anarchist bombings: Anarchists linked to Luigi Galleani exploded a bomb in front of U.S. Attorney General A. Mitchell Palmer's home at 2132 R Street, NW, Washington D.C. In April of the same year, a mail bomb was intercepted and defused before it reached Palmer. He would go on to lead the Palmer Raids. July 28, 1932: Bonus Army Conflict: a group of 43,000 demonstrators – made up of 17,000 U.S. World War I veterans, together with their families and affiliated groups – gathered in Washington, D.C. to demand early cash redemption of their service certificates. U.S. Attorney General William D. Mitchell ordered the group to be removed from all government property. Washington police, met with resistance, shot at the protestors, and two veterans were wounded and later died. President Herbert Hoover then ordered the U.S. Army to clear the marchers' campsite. Army Chief of Staff General Douglas MacArthur commanded a contingent of infantry and cavalry, supported by six tanks. MacArthur's troops attacked the makeshift camp with tear gas and set fire to the huts and lean-tos of the veterans and their families, injuring 55.Paul Dickson and Thomas Allen, "The Bonus Army: An American Epic," (Walker Books, 2006), pp. 182-183Time, 8 Aug. 1932, "Battle of Washington," archived at The Bonus Army veterans and their families were driven out and their shelters and belongings burned. November 1, 1950: Attempted assassination of Harry S. Truman: Griselio Torresola and Oscar Collazo, members of the Puerto Rican Nationalist Party, attempted to assassinate President Harry S. Truman at Blair House, killing White House Police officer Leslie Coffelt in the attempt. President Truman was staying there during the renovation of the White House. March 1, 1954: United States Capitol shooting: Puerto Rican nationalists led by Lolita Lebrón shot and injured five members of the House of Representatives during an immigration debate. They wanted to highlight their desire for Puerto Rican independence from the U.S. The assailants were arrested, tried and convicted in federal court, and imprisoned. In 1978 and 1979, their sentences were commuted by President Jimmy Carter; all four returned to Puerto Rico. April 4–8, 1968: Washington, D.C., riots: Following the Assassination of Martin Luther King Jr. on April 4, 1968, a four-day period of violent civil unrest erupted near the intersection of 14th and U Streets NW. Approximately 200 stores had their windows broken and 150 stores were looted, most of them emptied. Thirteen people were killed. May 10, 1970: A single homemade bomb, enclosed in a briefcase, exploded at the entrance to the National Guard Association of the United States. Windows in the building and surrounding area were blown out. The bombing occurred the night following a massive demonstration in D.C protesting the U.S. incursion into Cambodia. The radical left militant group called the Weather Underground Organization claimed responsibility for the attack. March 1, 1971: A bomb exploded in the United States Capitol, causing an estimated $300,000 in damage. The Weather Underground Organization claimed credit for the bombing, which was done in protest the U.S. bombing of Laos. January 18, 1973: Hanafi Muslim massacre: Several affiliates of the Black Mafia traveled to a house purchased for a group of Hanafi Muslims and murdered five children and two men. The target of the attack was Hamaas Abdul Khaalis, a former leader and critic of the Nation of Islam, who mailed letters to the ministers of all fifty mosques criticizing Elijah Muhammad. Seven individuals of the Black Mafia were tried and convicted. Khaalis would later lead the Hanafi Siege in 1977 to bring awareness to the killings. January 29, 1975: A device exploded in the third-floor women's bathroom of the U.S. Department of State, causing several walls to collapse and creating damage on five floors of the building. Damage was estimated at $350,000. A bomb threat was called into the Washington Post several minutes before the blast by the radical group the Weather Underground Organization. The group cited the continued war in Vietnam and Cambodia and the continued U.S. support for those governments.