The initial attack was broad and too weak to be effective yet yield many casualties on both sides. General Sherman's division was hit hardest and the Confederates pushed them back passed Shiloh Church. Reinforcements were slow to arrive. Poor coordination between Grant and his reserve troops caused them to become confused and take a different route. The reserves did not arrive until evening when the fighting was nearly over. The Confederates suffered heavy casualties along the Sunken Road, nick-named the Hornet's Nest because of the heavy rifle fire. The Union position held for 7 hours, but when Confederate cannons were brought to bear, the result was General Prentiss' surrender of his division.
This sacrifice afforded Grant time to build a strong defense at Pittsburg Landing. General Johnston was shot in the leg in Peach Orchard but refused treatment to allow doctors to help captured Union soldiers. He bled to death shortly thereafter. With Johnston's death, the Confederates were not at a severe disadvantage because Beauregard, who had been at the rear of the assault, did not have a clear idea of the state that the Union troops were in at this time. Because Beauregard did not put enough pressure on the Unions flanks, Union troops were able to regroup and form a defensive line around Pittsburg Landing. With cannon and gunboat support on the river, the Confederates' final charge was repulsed. As night fell, they had only been able to push Grant east towards the river instead of to the swamps where they could have easily been slaughtered.
The night was shattered with the cries of the wounded and the shells from the gunboats, disturbing soldiers' sleep on both sides. General Beauregard believed that he had won, but Union reinforcements arrived during the night and the battle resumed with the Confederates outnumbered. The fighting was intense and during the battle, Confederate troops were mixed up and uncoordinated. Union troops advanced, driving the Confederates south. Through the afternoon, Beauregard pulled back to Shiloh Church and held Union forces at bay until 5 P.M. when he withdrew toward Corinth, abandoning the position and in full retreat.
The next day, Sherman was sent by Grant to confirm the Confederate retreat and was nearly captured when coming upon a Confederate camp and field hospital. During the skirmish of Fallen Timbers Colonel Nathan Bedford Forrest was severely wounded. Despite this attack there was no sign that Confederate forces were regrouping to resume an attack on Pittsburg Landing.
Although this was a Union victory, General Grant was criticized for his lack of preparation and losing so many troops. He was also accused of being drunk, but President Lincoln defended Grant because he was a fierce fighter and tactical genius. The Battle of Shiloh was the bloodiest of the Civil War up to that point. It was a Union Victory that allowed the two Union Armies in Tennessee to combine.