On Friday, April 4, Gen. Albert S. Johnston’s army marched north from Corinth, Miss., into Tennessee, to attack the Federals under Maj. Gen. Ulysses Grant near Pittsburg Landing on the Tennessee River.
Heavy rain that night delayed the Confederate attack and slowed the march north. On the Peninsula southeast of Richmond, Maj. Gen. McClellan’s Union Army of the Potomac moved slowly north towards Yorktown, his massive army of over 112,000 confronted by some 15,000 Confederates and a weak line of fortifications along the Warwick River.
The main Confederate army in Virginia, under Gen. Joseph E. Johnston (no relation to Gen. Albert Johnston) was slowly moving south from the Rappahannock River line to reinforce the meager Confederates on the Peninsula commanded by Maj. Gen. John B. McGruder. On the Mississippi River, at Island No. 10, the Federals had cut a canal through the tangled swamps near New Madrid, Mo. so that they could move small boats with troops around the forts on the island. This was one of the very instances during the war where a canal actually worked. In a heavy thunderstorm, the Federal gunboat Carondolet ran past the Confederate batteries of the island.
The Federal siege of Yorktown began on April 5, when Gen. McClellan established his lines instead of attacking the Confederates there. He was concerned about the strength of the troops opposing his. In Tennessee, Gen. Johnston’s delay in reaching Pittsburg Landing delayed the attack against Grant’s forces for another day. President Davis wired Gen. Johnston: “I anticipate victory.” Union forces occupied Edisto Island, S.C., and in Nashville, Andrew Johnson, the Federal military governor of the state, suspended the mayor, aldermen, and councilmen of the city for refusing to take an oath supporting the Union.
Sunday, April 6: The start of a two-day battle at Shiloh Meeting House/Pittsburg Landing, Tennessee. Gen. Albert Johnston’s Confederates attacked the largely unprepared Federal army under Grant. The fighting was among the most intense and bloody of the war. Most of the killed had been hit in the head by bullets and shells; the wounded for the most part received their injuries in the arms and legs. Around 2:15 p.m., Gen. Johnston was struck by a bullet in the back of his right knee, severing the popliteal artery. In less than 15 minutes he bled to death, and Gen. P. G. T. Beauregard assumed command of the Confederate troops. Gen. Beauregard attempted to rally his army but called off the fighting until the next day.
That night a young soldier from Mississippi wrote, “Oh God forever keep me out of another such fight. I was not scared I was just in great danger.”
Overnight in the rain, Maj. Gen. Don C. Buell’s Federal troops arrived to reinforce Grant’s army; Gen. Beauregard expected reinforcements from Maj. Gen. Earl Van Dorn’s Confederates, then in Arkansas. After the intense fighting resumed on the morning of April 7, Beauregard learned that Van Dorn’s command would not arrive in time.
With the Federals having regained the ground they lost on April 6, Gen. Beauregard called off the fighting in early afternoon and withdrew his shattered army south towards Corinth. Grant chose to remain where he was and repair the human and physical damage his battered army had sustained. Casualties were enormous: of some 62,000 Union troops engaged, 13,047 were killed, wounded or missing. Of 40,000 Confederates engaged, losses numbered 10,700 – more than a fourth of the Confederate Army of Mississippi. Casualties at Shiloh up to that point in the war exceeded all of America’s previous war losses combined.