The Battle of Baton Rouge (1862) was a combined ground and naval action of the American Civil War fought on August 5, 1862, in East Baton Rouge Parish, Louisiana. Confederate forces under Maj. Gen. John C. Breckinridge tried to recapture Louisianas capital, but were driven back by Union troops supported by gunboats on the Mississippi River. The Union victory blunted Confederate plans along the lower river and foreshadowed the coming struggle for control at Port Hudson.

Quick definition and why it matters

The Battle of Baton Rouge was a Civil War engagement where Confederate troops attempted a surprise attack to seize Baton Rouge from a smaller Union garrison. Federal gunboats anchored on the Mississippi delivered decisive supporting fire, forcing a Confederate withdrawal. The fight secured Union presence on a key stretch of the river and influenced where both sides would fortify next.

Background: Baton Rouge after New Orleans

After Flag Officer David G. Farraguts capture of New Orleans in late April 1862, Union naval power dominated the lower Mississippi. Federal forces soon occupied Baton Rouge, the state capital, in May 1862. The occupation threatened Confederate logistics and morale in southeastern Louisiana and challenged Southern control of the river corridor. Determined to reverse Union gains, Confederate authorities planned an offensive combining infantry and the prized ironclad CSS Arkansasbattle-proven during the Vicksburg operationsto strike the isolated Baton Rouge garrison.

Armies, commanders, and the setting

Commanders

• Union: Brig. Gen. Thomas Williams (killed in action); command on the field passed to Col. Thomas W. Cahill of the 14th Maine.
• Confederate: Maj. Gen. John C. Breckinridge, leading a mixed force drawn from across the region.

Forces engaged

• Union strength: Approximately 2,500,000 soldiers in the immediate garrison, supported by several vessels of the West Gulf Blockading Squadron.
• Confederate strength: Roughly 3,500500 troops attacking in two main divisions.

Ground and river terrain

Baton Rouge sat on the east bank of the Mississippi and featured a patchwork of open fields, cane brakes, and urban edges. The citys western flank could be shielded by Union gunboats on the river. A heavy, early-morning fog on August 5 cloaked movements, added confusion, and allowed the Confederates to close on the Union camps.

The battle: August 5, 1862

Pre-dawn approach

Breckinridges men moved before dawn, aiming to surprise the Federals, roll up their lines, and hold the town until the expected arrival of CSS Arkansas could sweep Federal ships from the waterfront. The fog helped conceal the advance, but it also complicated coordination and delayed some formations.

Fighting around Magnolia Cemetery

Union troops formed hurried defensive lines as skirmishing erupted and grew into a general engagement around the citys northern approaches, including the area near Magnolia Cemetery. Brig. Gen. Thomas Williams worked to align regiments under chaotic conditionssome units were roused from camps under fireand used battery positions to slow the Confederate push. Williams was killed while directing the defense, and Col. Thomas W. Cahill assumed command at a critical moment.

Union regiments such as the 14th Maine, 21st Indiana, 6th Michigan, 7th Vermont, and others traded volleys at close range with Breckinridges advancing brigades. Artillery, including well-served Union light batteries, hammered road approaches and open fields. The fighting seesawed as fog lifted and visibility improved, revealing the proximity of the Mississippi River and the advantage it afforded the Federals.

Gunboats change the calculus

As the lines tightened, Union commanders tactically shifted their troops toward the riverbank, bringing them under the protective umbrella of naval fire. Federal shipsincluding the ironclad USS Essex and gunboats such as USS Kineo, USS Katahdin, and USS Sumterdelivered enfilading and suppressive bombardments into Confederate positions. The heavy guns made it costly for Breckinridges men to hold ground on the open approaches and prevented a decisive breakthrough.

Stalled assault and withdrawal

By late morning, the Confederate attack had lost momentum. Units had taken significant casualties, ammunition supplies were strained, and naval fire made further advances perilous. Though some Southern formations drove deep into the city outskirts and inflicted losses, they could not dislodge the Union line under the gunboats. Breckinridge ordered a withdrawal to avoid being shattered between infantry and river fire.

The missing hammer: CSS Arkansas and its fate

The Confederate plan banked on the feared ironclad CSS Arkansas to neutralize or disperse the Union flotilla at Baton Rouge. Mechanical troubles, however, plagued the ship. Attempting to reach the battlefield, the Arkansas suffered engine failure upriver on August 6. Pursued by Union vessels, her crew ran her aground and scuttled the ironclad to prevent capture, setting a dramatic end to one of the Confederacys most formidable river warships. Without the Arkansas, Confederate infantry at Baton Rouge had no answer to the concentrated naval guns that anchored the Union defense.

Casualties and losses

• Union: About 380 casualties (killed, wounded, and missing combined), including the loss of Brig. Gen. Thomas Williams.
• Confederate: Approximately 470 casualties overall, with heavy losses among units engaged in the most intense street and cemetery fighting.
• Naval losses: No Union vessels lost in action; the Confederate ironclad CSS Arkansas was destroyed the day after the battle due to mechanical failure and scuttling under pressure.

Note: Exact figures vary by source; the numbers above reflect commonly cited totals.

Why the Battle of Baton Rouge mattered

• Secured Union foothold on the lower Mississippi: Although the garrison was small, repelling the attack prevented an immediate Confederate resurgence at the state capital.
• Demonstrated the power of joint operations: The synergy of infantry and gunboats showcased how riverine fire support could shape ground outcomes.
• Foreshadowed Port Hudson: After the failed assault, Confederate planners concentrated on building a major stronghold farther upriver at Port Hudson, setting the stage for one of the wars longest sieges (1863).
• Neutralized a Confederate naval asset: The loss of CSS Arkansas deprived the Confederacy of a potent ironclad at a critical moment in the river campaign.

Aftermath and strategic consequences

Despite the battlefield victory, the Union soon found Baton Rouge difficult to hold due to disease, supply issues, and the demands of wider operations along the Gulf. Federal forces briefly evacuated the city later in August, consolidating strength around New Orleans and along the river. Confederates occupied Baton Rouge for a short period but turned their focus to fortifying Port Hudson, a commanding bluff about 25 miles north that offered better control of river traffic.

In the longer view, the battle underlined a pattern in the Western Theater: naval superiority on the Mississippi could offset smaller Union numbers on land, forcing Confederate operations to hinge on fortifications placed away from the reach or angles of gunboat fire. Less than a year later, combined Union offensives would invest Port Hudson and Vicksburg, ultimately securing the Mississippi River from end to end by mid-1863.

Key facts at a glance

• Date: August 5, 1862
• Location: East Baton Rouge Parish, Louisiana
• Result: Union victory
• Main commanders: Thomas Williams / Thomas W. Cahill (Union); John C. Breckinridge (Confederate)
• Notable naval element: Union gunboats on the Mississippi; CSS Arkansas failed to join and was scuttled the next day
• Estimated casualties: Union ~380; Confederate ~470

Tactical analysis: what decided the battle?

Union advantages

• Gunboat firepower: Heavy naval guns created a protective zone near the river, punishing Confederate concentrations and preventing flanking movements.
• Flexible defense: Union leaders pulled back methodically to align with naval arcs of fire, trading space for survivability and artillery support.
• Interior lines: Difficult urban and semi-urban terrain let defenders reposition batteries and reinforce hotspots quickly.

Confederate challenges

• Fog and friction: While the fog aided surprise, it also sowed confusion, delayed coordination, and complicated command control.
• Reliance on CSS Arkansas: Operational plans that assumed ironclad support left infantry exposed when the ship did not arrive.
• Exposure to enfilade: Open approaches near the river turned into killing zones once Union gunboats obtained clear lines of fire.

Visiting the battlefield today

While modern Baton Rouge has grown over the 1862 landscape, portions of the field around Magnolia Cemetery still convey the setting. Historical markers in the area interpret the fight, and local heritage sites in Baton Rouge include exhibits on Civil War Louisiana. Visitors can pair a walk through the cemetery area with riverfront stops to visualize how naval guns dominated the citys edge during the battle.

Timeline snapshot

• May 1862: Union forces occupy Baton Rouge after New Orleans falls.
• August 5, 1862 (pre-dawn): Breckinridge launches a surprise attack in heavy fog.
• Morningmidday: Fierce fighting near Magnolia Cemetery; Gen. Thomas Williams is killed; Union lines realign toward the river under gunboat protection.
• Late morning: Confederate assault loses momentum under infantry and naval fire; Breckinridge withdraws.
• August 6, 1862: CSS Arkansas suffers engine failure upriver and is scuttled under pressure from Union vessels.
• Late August 1862: Union briefly evacuates Baton Rouge; Confederates shift emphasis to fortifying Port Hudson.

Common questions answered

What triggered the Battle of Baton Rouge?

Confederate leaders sought to retake the Louisiana capital after Union occupation in May 1862. The plan paired a dawn ground assault with expected support from the ironclad CSS Arkansas to drive off Union gunboats and overwhelm the garrison.

Who won the Battle of Baton Rouge (1862)?

The Union won. Despite a strong Confederate attack, Federal infantry held their lines and, with help from gunboats on the Mississippi, forced a Confederate withdrawal.

How many soldiers fought, and what were the casualties?

Roughly 2,500,000 Union troops faced about 3,500500 Confederates. Casualties were approximately 380 for the Union and 470 for the Confederates, though figures vary by source.

How did Union gunboats influence the battle?

Gunboats such as USS Essex delivered powerful artillery support, enfilading Confederate lines and making it too costly to press the attack near the river. Their presence was the decisive factor once Union troops fell back under naval protection.

What happened to CSS Arkansas?

The ironclad failed to reach the fight on August 5 due to engine problems and was scuttled the next day after breaking down upriver while under pressure from Union vessels. Its loss deprived the Confederate assault of the naval punch it needed.

Why did the Union evacuate shortly after winning?

Illness, logistics, and broader operational priorities led the Union to consolidate forces closer to New Orleans and key river positions, even though they had defeated the Confederate assault at Baton Rouge.

What was the battles strategic impact?

The defeat discouraged Confederate attempts to hold Baton Rouge and redirected their efforts to fortify Port Hudson. Control of the Mississippi increasingly tipped toward the Union, culminating in the 1863 campaigns that opened the river.