After failing to capture Petersburg by assault, Grant's first objective was secure the three remaining open rail lines that served Petersburg and Richmond: the Richmond and Petersburg Railroad; the South Side Railroad, which reached to Lynchburg in the west; and the Weldon Railroad, also called the Petersburg and Weldon Railroad, which led to Weldon, North Carolina, and the Confederacy's only remaining major port, Wilmington, North Carolina. Grant decided on a wide-ranging cavalry raid (the Wilson-Kautz Raid) against the South Side and Weldon railroads, but he also directed that a significant infantry force be sent against the Weldon closer to his current position. Meade selected the II Corps, still temporarily commanded by Birney, and Wright's VI Corps.
On the same day the Union failed at the Crater, Confederate Lt. Gen. Jubal A. Early was burning the town of Chambersburg, Pennsylvania, as he operated out of the Shenandoah Valley, threatening towns in Maryland and Pennsylvania, as well as the District of Columbia. Robert E. Lee was concerned about actions that Grant might take against Early and sent the infantry division of Maj. Gen. Joseph B. Kershaw from Lt. Gen. Richard H. Anderson's corps and the cavalry division commanded by Maj. Gen. Fitzhugh Lee to Culpeper, Virginia, where they could either provide aid to Early or be recalled to the Richmond-Petersburg front as needed. Grant misinterpreted this movement and assumed that Anderson's entire corps had been removed from the vicinity of Richmond, leaving only about 8,500 men north of the James River. He determined to try again with an advance toward the Confederate capital led by Hancock. This would either prevent reinforcements from aiding Early or once again dilute the Confederate strength in the defensive lines around Petersburg.
On August 13, the X Corps, commanded by Maj. Gen. David B. Birney, and Brig. Gen. David McM. Gregg's cavalry division crossed pontoon bridges from Bermuda Hundred to Deep Bottom. The II Corps crossed by steamships the night of August 1314. Birney's X Corps troops successfully pushed aside pickets on the Kingsland Road, but were stopped by the fortifications on New Market Heights. The II Corps units moved slowly into position, suffering numerous deaths from heat stroke.
It was not until midday on August 14 that the Union made contact with the Confederates, manning rifle pits on the Darbytown Road just north of the Long Bridge Road. The Union generals were surprised at the Confederate strength. On the right, a full Confederate division commanded by Maj. Gen. Charles W. Field was dug in. Chaffin's Bluff was defended by a division under Maj. Gen. Cadmus M. Wilcox and reinforcements were arriving. Brig. Gen. Francis C. Barlow's 10,000 men in two divisions of II Corps attacked Fussell's Mill. They were able to drive away two Confederate cavalry regiments at the mill, but they were repulsed by Brig. Gen. George T. Anderson's brigade. When Field took Anderson's brigade from his right flank, it weakened the line in front of Birney's corps, which moved forward and occupied some of the Confederate entrenchments and captured four guns.
Although the Union attacks had been generally unsuccessful, they had some of the effect Grant desired. Lee became convinced that the threat against Richmond was a serious one and he dispatched two infantry brigades of Maj. Gen. William Mahone's division and the cavalry divisions of Maj. Gen. Wade Hampton and W.H.F. "Rooney" Lee. Hancock ordered Birney's corps to make a night march to join Barlow's end of the line. Birney's movement was delayed by difficult terrain for most of August 15 and Hancock's plan for an attack was abandoned for the day.
On August 16, Gregg's cavalry swept to the right and rode northwest on the Charles City Road toward Richmond. They found Rooney Lee's cavalry division blocking the road and a full day of fighting resulted. Confederate Brig. Gen. John R. Chambliss was killed during the fighting. The infantrymen of the X Corps had a better start to the day, as Brig. Gen. Alfred H. Terry's division broke through the Confederate line. Wright's Brigade was hit hard and retreated, opening a significant gap. The heavily wooded terrain prevented Birney and Hancock from understanding that they had reached a position of advantage and they were unable to exploit it before Field rearranged his lines to fill the gap and drive back the Federals.
Lee planned a counterattack against the Union right for 11 a.m. on August 18, but it was poorly coordinated and made no significant gains. On the night of August 20, Hancock withdrew his force back over the James. Union casualties were approximately 2,900 men, some due to heat stroke. Confederate casualties were 1,500.