Soldiers of the 39th Illinois dug these earthworks on the night of May 15, 1864 as part of the Army of the James under Maj. Gen. Benjamin F. Butler, who halted his army here after a demonstration toward Richmond. This position marked the far left of the Union line, which stretched east to the James River, while the main Confederate defenses protecting Drewry's Bluff stood about 2000 feet to the front. On May 16, 1864, Confederates under Gen. P.G.T. Beauregard attacked the Army of the James in a blinding fog. The attack was initially successful but stalled because of poor visibility and determined Union resistance on the right and center. Instead of counterattacking, Union commanders ordered a withdrawal to defensive positions in Bermuda Hundred, but in the confusion the 39th Illinois did not receive the order. Brig. Gen. Montgomery Corse's brigade attacked this part of the line, and after repulsing several assaults, the isolated 39th Illinois was overrun, with survivors fleeing south along the railroad toward Chester Station. The 15th Virginia Infantry was among the Confederate regiments that attacked the 39th Illinois, and men of that regiment, drawn from Richmond, Hanover, and Henrico, suffered more than 100 killed or wounded in their bloodiest day of the war. The Second Battle of Drewry's Bluff was the largest battle of the Bermuda Hundred Campaign, fought across a 3-mile-wide front by more than 28,000 troops and resulting in 3,000 Union and 1,000 Confederate casualties.