Late in the afternoon, around half past three, Grant ordered Thomas’s army forward. The target was the first of two Confederate lines on the ridge. The Confederates had split their force between a row of rifle pits (shallow trenches for infantry) dug along the base of the ridge, and a second line up on the crest at the top. Thomas’s men were to cross the open valley, take those lower trenches at the base, and pull Confederate attention off Sherman.
So they went. Across the open valley they came, some 23,000 to 24,000 men, straight into the lower rifle pits, which held only about 9,000 Confederate defenders. The Federals overran the trenches, and then found themselves in the worst possible place: pinned at the foot of the ridge, in the open, with the second Confederate line firing down on them from the crest several hundred feet above. Staying put meant being shot to pieces. Going back meant recrossing the valley under the same fire. Going up, straight up that brutal slope, meant closing with the guns that were killing them.
Nobody is entirely sure what the men were supposed to do once they had taken the lower trenches, and it changes who gets the credit. By one telling, the base was the only sanctioned objective: seize the first line and stop. By another, drawn from the National Park Service, Grant was already impatient before the assault even began, pressing Brig. Gen. Thomas J. Wood (North) about why his attack had not gone in:
“I ordered your attack an hour ago. Why has it not been made?… I order you to attack.”
Grant to Wood, before the assault
The surviving record cannot fully settle which it was, and standing where the men stood it almost did not matter. The position made the decision for them. Pinned and furious at the bottom of the ridge, the soldiers of the Army of the Cumberland made the choice their generals had not made for them.