Jackson had effected a junction with Lee, Hill was selected to relieve his tired troops by passing rapidly to his left and turning the extreme right of the enemy. A. P. Hill, Longstreet, Whiting and Jackson had successively moved upon the double lines of infantry and artillery posted on a range of hills behind Powhite creek from the McGehee to the Gaines house. The approach of the attacking columns of A. P. Hill and Whiting was in part over a plain about 400 yards wide, and was embarrassed by abattis and ditches in front of the first line. The struggle along the front of these divisions and that of Longstreet had become doubtful, and almost desperate, when the troops of Jackson and Hill created a diversion by engaging the extreme right of the enemy. The first of the lines of entrenchments had been taken, and Longstreet, Hood, Laws and other brave leaders, were moving on the last stronghold in the enemy's center, when the victorious shouts of Garland's and G. B. Anderson's brigade of Hill's division were followed by the rapid retreat of the enemy, and the surrender first of the ridge at the McGehee house and then of their whole line. Thus did it fall to the lot of Hill once more to strike a decisive blow at a critical moment. But claiming for him this distinction among a host of heroic commanders, it is proper that I should rely on the evidence of the lamented Garland, who sealed his devotion to the cause with his heart's blood at South Mountain, and the corroborating accounts of Hill's superiors from Jackson to President Davis, not upon my own assertion.
The effect of our appearance at this opportune moment upon the enemy's flank, cheering and charging (said Garland in his report), decided the fate of the day. The enemy broke and retreated, made a second stand, which induced my immediate command to halt under cover of the roadside and return the fire, when charging forward again we broke and scattered them in every direction.This discomfiture uncovered the left of the fortified line, and left no obstacle  between Hill and the McGehee house. (Series 1, Volume XI, Part 2, page 626 of Official Records.) General Jackson's language is not less unmistakable: ‘Again pressing forward the Federals again fell back, but only to select a position for more obstinate defence, when at dark—under the pressure of our batteries, which had then begun to play with marked effect upon the left, of other concurring events of the field and of the bold and dashing charge of General Hill's infantry, in which the troops of General C. S. Winder joined—the enemy yielded the field and fled in confusion.’ Of the part taken by Hill, General Lee said in his report (Series 1, Volume XI, Part 2, page 493, Official Records): ‘D. H. Hill charged across the open ground in his front, one of his regiments having first bravely carried a battery whose fire enfiladed his advance. Gallantly supported by the troops on his right, who pressed forward with unfaltering resolution, he reached the crest of the ridge (above the McGehee house), and after a sanguinary struggle broke the enemy's line, captured several of his batteries and drove him in confusion towards the Chickahominy until darkness rendered further pursuit impossible.’ As Mr. Davis (2 Rise and Fall, C. G., page 138) adopts the exact language of General Lee, it is needless to reproduce it a second time. General McClellan refers to the report of Fitz John Porter who was in command, for a detailed account of the affair at Gaines' Mill. Porter admits that the withdrawal of his line was caused by the retreat on his right, but insists that the demoralization was due entirely to the stampede of the Federal cavalry, who were mistaken, as they fell back on the infantry line, for rebels. More candid or better informed than General Porter, the French Princes, who served on his staff on that day, admit that the charge of Hill and the discomfiture of the enemy's right necessitated the abandonment of their line of entrenchments. If to double the right flank of an army suddenly back so as to expose to an enfilade the flank of his last and strongest line of entrenchments is to make his position untenable, then Hill's charge was indeed decisive of the struggle at Gaines' Mill. Crossing the Chickahominy on the night of the 29th in the advance of Jackson's corps, D. H. Hill passed Savage Station where he took 1,000 prisoners, exclusive of 3,000 in and connected with the Federal hospital. The progress of Jackson was arrested by obstructions and the stubborn resistance at White Oak swamps, and he failed to effect a junction with Longstreet till after the fight at Frasier's farm.