Virginia, essentially quiet since Robert E. Lee’s retreat from Gettysburg in July, heated up in mid-September 1863 as General George Meade’s Army of the Potomac occupied Culpeper Court House. Meade’s move from the Rappahannock to the Rapidan River was the result of Jefferson Davis’ detaching James Longstreet’s corps from Lee and temporarily reassigning it to support Braxton Bragg’s army now in northern Georgia.
On Thursday, September 10, 1863 yet another Confederate state capital fell to Union occupation, as General Sterling Price’s Confederates withdrew to Arkadelphia and Rockport. In primarily a cavalry action, Union General Frederick Steele had driven across eastern Arkansas and toward Little Rock for the better part of a month; on September 9 Steele’s troops crossed a horseshoe bend in the Arkansas River east of Little Rock, effectively outflanking the city’s Confederate defenders.
At Charlestown, South Carolina, on Tuesday, September 8, 1863 Union naval vessels continued their bombardment of Confederate forts in and around Charlestown Harbor as Admiral John A. B. Dahlgren prepared for a small-boat operation by night against Fort Sumter. Independently, Union General Quincy Adams Gillmore prepared a similar, infantry assault against Sumter.
On Wednesday, September 9, 1863 Braxton Bragg’s Confederate Army of Tennessee abandoned Chattanooga and withdrew southward into Georgia. Federal troops under General William Rosecrans immediately entered the city, while other units marched southward against Bragg.
Union General Nathaniel Banks intended to invade Texas at Sabine Pass on the Texas-Louisiana border; from there Federal troops could control East Texas. On Tuesday, September 8 four Union gunships and transports carrying 5000 troops moved into Sabine Pass; opposing the Union fleet was a poorly constructed, Confederate earthwork manned by a handful of Confederate troops under Lieutenant Dick Dowling.
The Union gunboats opened fire, and the Confederates responded, striking and grounding two gunboats and forcing the surrender of 200 prisoners.
At Charlestown, South Carolina during the night of September 6, 1863 the embattled Confederate garrisons of Fortress Wagner and Battery Gregg, under Union shelling since early July, were quietly evacuated and relocated around Charlestown’s perimeter, because Confederate commander Pierre Beauregard believed that a major Union infantry assault was pending and he doubted that an assault could be stopped by Wagner and Greggs’ Confederate defenders.
On Saturday, September 5, 1863 troops entered the Laird Shipyards in England and seized two ironclads nearing completion which rumors had destined for sale to the Confederate States of America. For months both the American minister to England Charles Francis Adams and Washington had expressed concerns over the construction of these vessels.
When Simon Buckner’s Army of Eastern Tennessee was ordered to join Braxton Bragg’s forces at Chattanooga, Tennessee, Buckner left only token forces to defend the Cumberland Gap through the mountains and a brigade to defend the city of Knoxville.
On Wednesday, September 2, 1863 a cavalry unit under the command of Union General Ambrose Burnside exploited the Confederates’ weaknesses and entered Knoxville, largely unopposed. The next day Burnside and his main force entered the city, warmly welcomed by the city’s Unionist population.
Early in September 1863 William Roscrans’ Union Army of the Cumberland crossed the Tennessee River in preparation of moving against Chattanooga and her Confederate defenders.
Fearing the worst for his state and appealing to Jefferson Davis for assistance, Tennessee’s Confederate Governor Isham G. Harris received assurances from Davis that both reinforcements and arms were being sent to Braxton Bragg’s threatened army.
On September 1 and 2, 1863 at Charlestown, South Carolina the Federal bombardment of Confederate defenses resumed with a total of 627 shot fired against Fortress Wagner on Morris Island and against Fort Sumter in Charlestown’s harbor.