April 12, 1861 - Fort Sumter fired upon in Charleston, South Carolina.
April 14, 1861 - Fort Sumter surrendered.
April 15, 1861 - President Lincoln calls for volunteers
A Proclamation by the President of the United Stales.
Whereas, the laws of the United States have been for some time past and now are opposed, and the execution thereof obstructed, in the States of South Carolina, Georgia, Alabama, Florida, Mississippi, Louisiana, and Texas, by combinations too powerful to be suppressed by the ordinary course of judicial proceedings, or by the powers vested in the marshals by law: now, therefore, I, Abraham Lincoln, President of the United States, in virtueof the power in me vested by the Constitution and the laws, have thought fit to call forth, and hereby do call forth, tho militia of the several States of the Union to the aggregate number of 75,000, in order to suppress said combinations and to cause the laws to be duly executed.
The details for this object will be immediately communicated to the State authorities through the War Department. I appeal to all loyal citizens to favor, facilitate, and aid this effort to maintain the honor, the integrity, and existence of our national Union, and the perpetuity of popular government, and to redress wrongs already long enough endured. I deem it proper to say that the first service assigned to the forces hereby called forth, will probably be to repossess the forts, places, and property which have been seized from the Union; and in every event the utmost care will be observed, consistently with tho objects aforesaid, to avoid any devastation, any destruction of, or interference with, property, or any disturbance of peaceful citizens of any part of the country; and I hereby command the persons composing the combinations aforesaid, to disperse and retire peaceably to their respective abodes, within twenty days from this date.
Deeming that the present condition of public affairs presents an extraordinary occasion, I do hereby, in virtue of the power in me vested by the Constitution, convene both houses of Congress. The Senators and Representatives are, therefore, summoned to assemble at their respective Chambers at twelve o’clock, noon, on Thursday, the fourth day of July next, then and there to consider and determine such measures as, in their wisdom, the public safety and interest may seem to demand.
In witness whereof, I have hereunto set my hand, and caused the seal of the United States to be affixed.
Done at the City of Washington, this fifteenth day of April, in the year of our Lord, one thousand eight hundred and sixty-one, and of the independence of the United States the eighty-fifth.
ABRAHAM LINCOLN.
By the President.
William H. Seward, Secretary of State.

CARL RUSSO/Staff photo. Re-enactment participants in The Famous Olde Sixth Company I Massachusetts Militia of Lawrence Mass. from left, Sean Sweeney of Lawrence; Christian Padron of Lawrence; flag bearer, Morrgan Sweeney-Charlton, 17, and a sophomore at Central Catholic High School and Joe Bella of Methuen demonstrate a formation used to put down a mob while visiting the graves of Sumner Needham and his widow, Hannah in Lawrence’s Bellevue Cemetery. Sumner was a member of the Sixth Co. I Mass. Militia when he was killed by a secession mob in Baltimore in April 1861. The militia was traveling through Baltimore on its way to Washington to defend the capital at the start of the Civil War. The Lawrence militia members will travel to Baltimore on the weekend of April 16 to participate in events to commemorate the 150th. anniversary of the Civil War and the mob attack on the Militia that killed Sumner.
April 17, 1861 - Virginia secedes from the Union.
April 18, 1861 - Harper’s Ferry, Virginia evacuated.
April 19, 1861 - 6th Massachusetts Volunteer Infantry, while answering the call-to-arms attacked in Baltimore, Maryland while en route to Washington.
April 19, 1861 - President Lincoln declares a blockade of the Southern Coast.
April 20, 1861 - Robert E. Lee resigns from the United States Army.
April 23, 1861 - Robert E. Lee assumes command of the Virginia State forces.
April 29, 1861 - First Minnesota Volunteer Infantry mustered in at Fort Snelling, Minn.
April 29, 1861 - Confederate Provisional Congress convenes for its second session.
April 30, 1861 - Colonel Thomas Jonathan Jackson occupies Harper’s Ferry, Virginia.