It was one of the bloodiest sieges of the war—a siege that drove men, women, and children to seek shelter in caves underground; where shortages of food drove people to eat mules, rats, even pets; where the fighting between armies was almost as nothing to the privations suffered by civilians who were under constant artillery bombardment—every pane of glass in Vicksburg was broken.

But the drama did not end there. Vicksburg was a vital strategic point for the Confederacy. When the city fell on July 4, 1863, the Confederacy was severed from its western states of Texas, Louisiana, and Arkansas. Its fall was simultaneous with General Robert E. Lee’s shattering defeat at Gettysburg far to the north. For generations, July 4 was no day to celebrate for Southerners. It was a day or mourning—especially for the people of Mississippi.

Yet this epic siege has long been given secondary treatment by popular histories focused on the Army of Northern Virginia and the Gettysburg campaign. The siege of Vicksburg was every bit as significant to the outcome of the war. The victorious Union commander, Major General Ulysses S. Grant, learned hard lessons assaulting Vicksburg, “the Confederate Gibraltar,” which he attempted to take or bypass no less than nine times, only to be foiled by the outnumbered, Northern-born Confederate commander, Lieutenant General John C. Pemberton.

At the end, despite nearly beating the odds, Pemberton’s army was left for dead, without reinforcements, and the Confederacy’s fate was ultimately sealed.

This is the incredible story of a siege that lasted more than forty days, that brought out extraordinary heroism and extraordinary suffering, and that saw the surrender of not just a fortress and a city but the Mississippi River to the conquering Federal forces.