Tuesday April 15, 1861
In Washington, Lincoln issued a proclamation announcing the existence of an "insurrection," and calling forth 75,000 of the "the militia of the several States of the Union." The proclamation also summoned Congress to a special session to convene on July 4, 1861.
Bibliography: Swanberg, First Blood, pp. 330-32; Current, Lincoln and the First Shot, p. 157.