The Siege of Petersburg was one of the most important military campaigns of the American Civil War. It lasted approximately nine and a half months, from June 15th, 1864 to April 2nd, 1865, and saw Union forces under General Ulysses S. Grant gradually surround and cut off the city of Petersburg, Virginia, which was a critical railroad hub supplying the Confederate capital of Richmond. The siege ended when Grant broke through the Confederate defensive lines in April of 1865, forcing General Robert E. Lee to abandon both Petersburg and Richmond and leading directly to Lee’s surrender at Appomattox Court House on April 9th, 1865.
What Was the American Civil War?
The Siege of Petersburg took place during the final year of the American Civil War, which was one of the most significant conflicts in the history of the United States. The Civil War was fought between the Northern states, known as the Union, and the Southern states, known as the Confederacy, from 1861 to 1865. The war was mainly fought over the issue of slavery, which had divided the country for many years. By the summer of 1864, Grant had been pushing his army south through Virginia in a series of battles known as the Overland Campaign. His goal was to destroy Lee’s Army of Northern Virginia and capture Richmond, the Confederate capital. Petersburg was the key to Richmond. Five railroad lines ran through Petersburg, bringing food, supplies, and soldiers to Richmond and to Lee’s army. Grant understood that if he could capture Petersburg, Richmond would fall soon after and the war in the East would effectively be over.
Siege of Petersburg – Background and the Move to Petersburg
After the costly Battle of Cold Harbor in early June of 1864, Grant made a bold decision. Rather than attacking Lee directly again, he secretly moved his entire army away from Cold Harbor and south across the James River, aiming to strike Petersburg before Lee could respond. The move was one of the most skillful of the entire war. Grant’s engineers built a massive pontoon bridge over 2,000 feet long across the James River and the army crossed in just a few days without Lee realizing what was happening.
Petersburg at this point was defended by Confederate General P.G.T. Beauregard with as few as 2,200 soldiers. Union forces began attacking the city on June 15th, 1864, and for several days had a real opportunity to capture it before Lee arrived. However, poor coordination among Union commanders and exhausted troops allowed the window to close. Lee’s army began arriving at Petersburg on June 18th. With the arrival of Lee’s veterans, the Union forces could no longer take the city by direct assault and Grant settled in for a siege.
Siege of Petersburg – The Siege Begins
Once both armies dug in around Petersburg, they quickly built an extensive network of trenches and fortifications. The trench lines eventually stretched for approximately 30 to 40 miles, running east and south of Petersburg and north toward Richmond. The conditions in the trenches were difficult for soldiers on both sides. They faced constant artillery fire, sniping, and the misery of living in cramped and often flooded earthworks through the summer heat and winter cold.
Grant’s strategy was not simply to wait Lee out. He launched a series of major offensives aimed at extending his lines further west and south to cut the railroad lines that kept Petersburg and Richmond supplied. Each time Grant extended his lines, Lee was forced to stretch his own shrinking army thinner to match. By the end of 1864, Lee’s army had been reduced to approximately 45,000 soldiers while Grant had approximately 110,000. The Confederate soldiers were hungry, poorly supplied, and increasingly demoralized as the months passed.
Siege of Petersburg – The Battle of the Crater
The most dramatic single event of the entire siege took place on July 30th, 1864. A regiment of Pennsylvania coal miners in the Union army had proposed digging a long tunnel underneath the Confederate defensive line and packing it with explosives. After weeks of digging, miners completed a tunnel approximately 510 feet long directly under a Confederate position. On the morning of July 30th, approximately 8,000 pounds of black powder were detonated. The explosion killed around 300 Confederate soldiers and created a large crater in the earth. Union soldiers poured forward to attack through the gap in the Confederate line.
The assault quickly went wrong. Union soldiers rushed into the crater itself rather than around it, and became trapped in the hole. Confederate defenders recovered from the shock of the explosion and organized a fierce counterattack. The fighting at the crater became some of the most brutal of the entire siege. By the time the assault ended, the Union had suffered approximately 4,000 casualties while the Confederates suffered approximately 1,800. Grant called it a stupendous failure. The Confederate line held and the opportunity was lost.
Siege of Petersburg – Final Months
Through the fall and winter of 1864 and into early 1865, Grant continued to extend his lines to the west, steadily cutting off the supply routes into Petersburg. By February of 1865, only one railroad line, the South Side Railroad, was still open to the Confederates. Lee’s army was growing weaker by the month. Desertion increased as soldiers went hungry and received letters from home describing the hardship their families were suffering.
On March 25th, 1865, Lee made a desperate attempt to break out of the siege by attacking a Union position called Fort Stedman on the eastern end of the line. The attack initially succeeded in capturing the fort but Union counterattacks quickly drove the Confederates back with heavy losses. Lee’s last offensive effort had failed.
On April 1st, 1865, Grant sent a large force under General Philip Sheridan to attack the far western end of the Confederate line at a place called Five Forks. The attack was a complete success. The Confederate right flank was crushed and the South Side Railroad was cut, eliminating the last supply line into Petersburg. On April 2nd, Grant ordered a general assault along the entire Confederate line. Union soldiers broke through the Confederate defenses in several places. General A.P. Hill, one of Lee’s most trusted corps commanders, was killed during the fighting. Lee sent word to Confederate President Jefferson Davis that Petersburg and Richmond could no longer be held and that both cities must be abandoned.
Siege of Petersburg – Aftermath
Lee evacuated his army from Petersburg and Richmond during the night of April 2nd, 1865. Union troops entered both cities on April 3rd. Grant immediately ordered his army to pursue Lee’s retreating forces to the west. Within a week, Union forces had cut off Lee’s escape routes and surrounded the remnants of the Army of Northern Virginia. On April 9th, 1865, Lee met Grant at Appomattox Court House, Virginia, and surrendered his army, effectively ending the Civil War in the Eastern Theater.
The total casualties of the Siege of Petersburg were approximately 42,000 Union soldiers and 28,000 Confederate soldiers, for a combined total of approximately 70,000 over the nine and a half months of the campaign.
Significance of the Siege of Petersburg
The Siege of Petersburg was one of the most significant campaigns of the entire American Civil War. Its outcome determined the fate of Richmond, the Confederate capital, and effectively ended the war in the East. The siege is also historically significant because of the style of warfare it introduced. The miles of trenches, the underground tunnels, the long periods of static fighting, and the grinding attrition of two armies facing each other across fixed lines all foreshadowed the trench warfare that would become familiar to the world in World War I fifty years later. The Siege of Petersburg showed that the Civil War had entered a new era of warfare, one defined not just by battles in open fields but by the slow and costly struggle to break through fortified lines that neither side could easily abandon.
