Fort Blakeley fell on the afternoon of April 9, 1865. That same afternoon, in a village in Virginia, Robert E. Lee was signing the surrender of the Army of Northern Virginia to Grant. The two events were hours apart and a thousand miles apart, and neither side at Blakeley had any idea the other had happened. It has often been called the last major battle of the Civil War, and the last time two large forces of the war fought a stand-up engagement, the rebellion was already, in its heart, over.

The fall of Blakeley sealed Mobile. With the eastern-shore forts gone and his outer works lost, Major General Dabney H. Maury (South) could not hold the city, and he pulled his remaining troops out rather than be trapped. On April 12, 1865, the mayor of Mobile rode out and surrendered the town to Canby’s forces. The last significant Confederate port on the Gulf of Mexico, the harbor the United States Navy had been trying to close since the summer before, was finally in Union hands.

There is a hard symmetry in how the western war ended. The Confederacy had gone to war to keep Black people enslaved. The earthwork that fell in its last major battle was carried, in good part, by Black soldiers, thousands of them, many of them men who a few years earlier had been somebody’s legal property in this very part of the South, now crossing a minefield in United States uniforms to take the wall. The 5,000 men of the United States Colored Troops at Blakeley made up one of the heaviest concentrations of Black soldiers in any battle of the war, and they were there at the end of it, on Alabama ground, helping pull down the last fort of a country built to own them.

The rest came quickly. With Lee gone in Virginia and the western armies surrendering one after another through the late spring, the war wound down for good. Fort Blakeley does not carry the weight of Gettysburg or Antietam in the country’s memory, and the men who fought there did not know they were fighting the last of it. But the last large charge of the Civil War went in across an Alabama field at dusk, against a wall held by teenagers and the worn-down survivors of older battles, and it was carried by the very men the whole war had been fought over. The fighting that had begun four years before at a fort in a Southern harbor ended at another one, with the question that started it answered for good.