Following the surrender of Fort Sumter in Charleston, South Carolina, on April 14, 1861, new American president Abraham Lincoln declared that "an insurrection existed," and called for 75,000 troops to be called up to quash the rebellion. The move sparked resentment in many other southern states, which promptly moved to convene discussions of secession. The Virginia State Convention passed "an ordinance of secession" and ordered a May 23 referendum to decide whether or not the state should secede from the Union. The U.S. Army responded by creating the Department of Washington, which united all Union troops in the District of Columbia and Maryland under one command.