The Baltimore riot of 1861 (also called the "Pratt Street Riots" and the "Pratt Street Massacre") was a civil conflict on Friday, April 19, 1861, on Pratt Street, in Baltimore, Maryland, between antiwar "Copperhead" Democrats (the largest party in Maryland) and other Southern/Confederate sympathizers on one side, and members of the primarily Massachusetts and some Pennsylvania state militia regiments en route to the national capital at Washington called up for federal service, on the other. The fighting began at the President Street Station, spreading throughout President Street and subsequently to Howard Street, where it ended at the Camden Street Station. The riot produced the first deaths by hostile action in the American Civil War and is nicknamed the "First Bloodshed of the Civil War".
In 1861, most Baltimoreans were anti-war, and did not support a violent conflict with their southern neighbors. Many sympathized passionately with the Southern cause. In the previous year's presidential election, Abraham Lincoln had received only 1,100 of more than 30,000 votes cast in the city. Lincoln's opponents were infuriated (and supporters disappointed) when the president-elect, fearing an infamous rumored assassination plot, traveled secretly through the city in the middle of the night on a different railroad protected by a few aides and detectives including the soon-to-be famous Alan Pinkerton in February en route to his inauguration (then constitutionally scheduled for March 4) in Washington, D.C. The city was also home to the country's largest population (25,000) of free African Americans, as well as many white abolitionists and supporters of the Union. As the war began, the city's divided loyalties created tension. Supporters of secession and slavery organized themselves into a force called "National Volunteers" while Unionists and abolitionists called themselves "Minute Men".
The American Civil War began on April 12, one week before the riot. At the time, the slave states of Virginia, North Carolina, Tennessee, and Arkansas had not yet seceded from the U.S. The status of Delaware, Maryland, Missouri, and Kentucky (later known as "border states"), remained unknown. When Fort Sumter fell on April 13, the Virginia legislature took up a measure on secession. The measure passed on April 17 after little debate. Virginia's secession was particularly significant due to the state's industrial capacity. Sympathetic Marylanders, who had supported secession ever since John C. Calhoun spoke of nullification, agitated to join Virginia in leaving the Union. Their discontent increased in the days afterward when Lincoln put out a call for volunteers to serve 90 days and end the insurrection.