While Sheridan was out on raiding the Virginia Central Railroad, and trying to attract the attention of Robert E. Lee. Grant and Meade began to put their plan to attack Petersburg into action. The movement began on the night of June 12, and work began on an over 2000 foot pontoon bridge across the James River. The Union army began crossing on June 14, and all the men were not across until the 18th. However, they did not wait that long to strike at Petersburg. The advance on that town began on June 15. Leading the Federal army was Benjamin Butler's Army of the James, which had already failed to capture Petersburg once during the Bermuda Hundred Campaign.
Petersburg was very weakly held. Lee had not realized that Grant was attacking Petersburg with his entire army, and so remained north of the James. The commander at Petersburg was P. G. T. Beauregard. He still had to deal with Butler on the Bermuda Hundred, so he only had 2,200 men to hold the Petersburg defenses.
As “Baldy” Smith, commander of the XVIII corps, approached Petersburg on June 15th, 150 years ago today, he was worried about the strength of its entrenchments. There were six foot high breastworks surrounded by a ditch six feet deep and fifteen wide. In front of this obstacle was a row of felled trees with branches sharpened to delay the attackers while they were shot at from the walls. Smith spent time examining the positions, and looking for weak spots. By 4 pm he had decided to attack with heavy skirmish lines, hoping that they would not suffer heavily from Confederate fire during the charge. He set the launch off time at 5 pm, but it was discovered that no one had told the artillery chief of the plans. The guns were needed for supporting fire while the infantry attacked. The artillery horses had been sent away for water, and could not pull the guns into position. Smith delayed the attack until 7 pm, when his troops were able to move forward.
When Smith's men charged these works, they found them much less formidable than they had imagined. As they pushed backed the skirmishers, crossed the abatis and climbed the ditch, they quickly gained the walls meeting little resistance. Many batteries were captured by Smith's advance over more than a mile of entrenchments. At this point, however, Smith halted the assault. The Confederates fell back to a weaker line, and Smith thought it likely that Lee had crossed the James and was in his front. He wanted to prepare his men to meet a counter-attack, not continue forward. Winfield Scott Hancock arrived, ahead of his corps, and although the senior officer on the field and normally aggressive, he acquiesced to Smith's decision. No more attacks would be made that night.