In the aftermath of President Abraham Lincoln's call for troops to put down the insurrection in South Carolina, many Virginians who had opposed secession on its merits quickly changed their minds about secession for practical reasons. The question was no longer whether secession was wise, legal, necessary, or in Virginia's interest; the question became which side to take. Perceiving Lincoln's attempt to resupply Fort Sumter as a deliberate attack on a slave state and his call for volunteers as commencing war against the slave states, thirty-four members of the convention who had voted against secession on April 4 changed their minds, as did two other members who had not voted on April 4 but who had indicated their opposition to secession at that time.
The convention went into secret session on April 16 and for two days allowed ten minutes for each member who wished to explain his vote. During the final debate Henry A. Wise placed a large pistol on his desk in the House of Delegates chamber, where the convention was meeting, and made a terrifying speech in favor of secession. Many of the Unionist delegates were in tears as they explained what a great mistake the convention was going to make or how much it pained them to have to change their minds and vote for secession. The men who continued to oppose secession argued that if Virginia took part in the war on the side of the lower South slave states, Virginia would become the principal battleground in the war, which would be a disaster for the state and also probably result in the destruction of slavery in Virginia. Members on both sides of the question also denounced Lincoln for waging war on the people of the lower South.
Late in the afternoon on April 17, the delegates voted 88 to 55 to submit an ordinance of secession to the voters for ratification or rejection on May 23, 1861. During the following two weeks 7 delegates who had voted against secession asked permission to change their votes in favor, and several delegates who had been absent on April 17 also recorded their votes in favor. Still, nearly a third of the elected delegates opposed secession even when it was clear that the secession crisis had become a civil war. They included most of the delegates from the Ohio Valley counties and northwestern Virginia and a majority from the Shenandoah and Potomac River Valleys. The only eastern men to vote against secession on April 17 were one delegate from Henrico County, the delegate from Accomack County, on the Eastern Shore, and the two delegates who represented Norfolk County and the city of Portsmouth.