On April 29, Union troops attempt to cross the Mississippi at Grand Gulf. The Union fleet bombards Confederate defenses for five hours, but Grant’s troops are repulsed. Grant moves farther south in search of a more favorable crossing point and eventually finds one in Bruinsburg. In the early morning hours of April 30, infantrymen of the Twenty-fourth and Forty-sixth Indiana Regiments step ashore on Mississippi soil. The two sides clash at Port Gibson and Raymond.
May 18. Looking for a quick victory and not wanting to give Pemberton time to settle his garrison, Grant orders an immediate assault. Of his three corps, only Maj. Gen William T. Sherman’s Fifteenth Corps, stationed northeast of the city, is in a position to attack.
As weeks go by, Pemberton’s defenders suffer from shortened rations, exposure to the elements, and constant bombardment from Grant’s army and navy gunboats. Reduced in number by sickness and casualties, the garrison of Vicksburg is spread dangerously thin. Civilians are hard hit, with many forced to live in crudely dug caves due to the heavy shelling.
June 25. Following Grant’s orders to dig tunnels and set explosives under the Confederate works, Union sappers detonate a mine with 2,200 pounds of black powder, causing a huge explosion. After more than 20 hours of hand-to-hand fighting in the 12-foot deep crater left by the blast, Union regiments are unable to advance and withdraw back to their lines. The siege continues.
Union victory. After a 47-day siege, Lt. Gen. John C. Pemberton’s Confederate troops surrendered to Gen. Ulysses S. Grant. Together with the Union victory at Gettysburg just a day before, Vicksburg marked a turning point in the fortunes of the Union army.
On July 7, 1863, three days after the fall of Vicksburg and four after a victory at Gettysburg, the president writes to his General-in-Chief: “Major Genl Halleck: We have certain information that Vicksburg surrendered to General Grant on the 4th of July. Now, if Gen. Meade can complete his work so gloriously prosecuted thus far, by the litteral(sic) or substantial destruction of Lee's army, the rebellion will be over. Yours truly, A. LINCOLN”