Vicksburg and the Mississippi: Splitting the Confederacy in Two - Decisive Battles of the American Civil War

Setting the Stage: Why Vicksburg Mattered

Two Crucial Places in 1863

In mid-1863, Gettysburg in Pennsylvania and Vicksburg in Mississippi shaped the war. Gettysburg drew attention in the East, but Vicksburg quietly decided control of the Mississippi River.

Vicksburg’s Geography

Vicksburg sat on high bluffs over a sharp bend in the Mississippi. From these heights, Confederate guns could hit any Union ship. As long as it held, the South kept a vital east-west link.

Union River Strategy

The Union goal in the West was full control of the Mississippi River. This would cut the Confederacy in two, block supplies from the West, and support the overall Anaconda Plan.

Last Major Obstacle

By early 1863, the Union held New Orleans, Memphis, and other key points. Vicksburg and nearby strongpoints were the last major Confederate barriers on the river.

Why Geography Matters

Rivers, bluffs, swamps, and railroads around Vicksburg shaped every choice General Ulysses S. Grant made. To understand the campaign, you must understand this terrain.

Grant’s Problem: Tough Terrain and Early Failures

Grant’s Challenge

Grant had to capture a fortress on high bluffs, surrounded by swamps and a powerful river. A direct attack risked disaster against strong Confederate defenses.

Early Attempts Fail

In late 1862 and early 1863, Grant tried direct approaches and canal projects near Vicksburg. Flooded lowlands, bayous, and forts stopped these efforts.

Hard Conditions

Union soldiers waded through mud and swamps, while disease spread. Northern critics questioned Grant’s ability after these apparent failures.

Learning from Failure

These setbacks taught Grant about the terrain and enemy positions. He saw that he must avoid the strongest defenses and find firmer ground.

Key Strategic Shift

Grant decided he needed to use Union naval power, move around Vicksburg instead of straight at it, and rely partly on local supplies. His persistence became a major advantage.

Union Riverine Warfare: Navy and Army Working Together

What Is Riverine Warfare?

The Vicksburg Campaign shows riverine warfare in action: using naval forces on rivers to support land operations and control key waterways.

Admiral Porter’s Fleet

Rear Admiral David D. Porter led Union gunboats and ironclads. They bombarded forts, moved troops and supplies, and guarded river supply routes.

Running the Vicksburg Batteries

In April 1863, Porter’s ships ran past Vicksburg’s guns at night. Some were damaged, but most got through, giving Grant naval support south of the city.

Joint Operations in Action

The navy ferried Grant’s troops across the river at Bruinsburg, brought supplies, and shelled Confederate positions. Army and navy acted as one team.

Strategic Edge

Union river control gave Grant choices the Confederates lacked. This kind of army-navy cooperation foreshadowed modern joint warfare.

The Bold Maneuver: Crossing South of Vicksburg

Going Around, Not Through

Grant chose to move around Vicksburg instead of attacking its strongest defenses. With the navy below the city, he marched his army down the west bank.

Crossing at Bruinsburg

On April 30, 1863, Grant’s army crossed at Bruinsburg. It was the largest amphibious operation in U.S. history up to that time, landing on firmer ground south of Vicksburg.

Cutting Loose from Supplies

After crossing, Grant cut himself off from his main supply base. He advanced quickly inland, using speed, surprise, and local resources to support his army.

String of Union Victories

Grant’s forces won at Port Gibson, Raymond, Jackson, and Champion Hill. These battles drove Confederate forces back and disrupted their supply and communication lines.

Vicksburg Isolated

By mid-May 1863, Grant had surrounded Vicksburg from the land side. The river fortress was now a trapped city, cut off from help to the east.

Map Thinking: Tracing Grant’s Route

Use this thought exercise to mentally map the Vicksburg Campaign. You do not need an actual map, but visualizing the movement will help you remember the key steps.

Picture the Mississippi River running roughly north to south.
Imagine Vicksburg on the east bank, sitting on high bluffs overlooking a bend in the river.
Now trace these moves in your mind:

A. Union forces north of Vicksburg try to come straight down the river and through swamps.
B. Admiral Porter’s ships run past the Vicksburg batteries at night to reach the river below the city.
C. Grant marches his army down the west bank to a crossing point at Bruinsburg.
D. Union troops cross to the east bank, then move inland toward Jackson and westward back toward Vicksburg.

Your task:

In 3–4 sentences, describe Grant’s route to a classmate as if you are giving directions on a map. Start with “First, he…” and explain how he ends up surrounding Vicksburg from the east.
Then, add 1 sentence explaining why crossing south of Vicksburg gave him an advantage.

If you have paper available, sketch a simple “S” curve for the river, mark Vicksburg on the east bank, and draw arrows showing the movements you just described.

From Assault to Siege: Life in the Trenches

Failed Assaults

In mid-May 1863, Grant tried direct assaults on Vicksburg’s defenses. On May 19 and 22, steep ravines and strong forts turned these attacks into bloody failures.

Shift to Siege Warfare

After heavy losses, Grant switched to a siege. He surrounded Vicksburg, cut it off from supplies, and aimed to wear down the defenders over time.

Life Inside Vicksburg

Civilians and soldiers dug caves into hillsides to escape shelling. Food ran low, and disease and malnutrition spread in the crowded, unsanitary city.

Union Siege Tactics

Union troops dug trenches and artillery positions, using zigzag saps and mining to inch closer and weaken Confederate defenses day by day.

Surrender on July 4

By early July, Confederate forces were starving and exhausted. On July 4, 1863, General Pemberton surrendered Vicksburg and its garrison to Grant.

Checkpoint: Why Did the Union Win at Vicksburg?

Answer this question to test your understanding of the main reasons for Union success at Vicksburg.

Which combination best explains why the Union succeeded in capturing Vicksburg?

Superiority in numbers alone; Grant simply overwhelmed the city with more soldiers.
A surprise cavalry raid and one decisive battle directly outside Vicksburg’s walls.
Joint army-navy cooperation, Grant’s bold maneuver south of the city, and a sustained siege that cut off supplies.
Confederate forces voluntarily abandoned Vicksburg to defend other cities along the Mississippi.

Show Answer

Answer: C) Joint army-navy cooperation, Grant’s bold maneuver south of the city, and a sustained siege that cut off supplies.

The Union victory at Vicksburg came from a combination of factors: close cooperation between the navy and army, Grant’s decision to cross south of Vicksburg and fight inland battles, and a determined siege that starved the city into surrender. Numbers alone or a single battle did not decide the campaign.

July 4, 1863: A Dual Turning Point

Two Events, One Date

Gettysburg ended on July 3, 1863, and Vicksburg surrendered on July 4, 1863. These back-to-back events made early July 1863 a key turning point.

Gettysburg’s Impact

Gettysburg stopped Lee’s invasion of the North and damaged the offensive power of the Confederate Army of Northern Virginia in the Eastern Theater.

Vicksburg’s Impact

Vicksburg’s fall gave the Union full control of the Mississippi River, removing a major Confederate stronghold in the Western Theater.

Splitting the Confederacy

With Vicksburg and later Port Hudson, the Union cut the Confederacy in two, isolating Texas, Arkansas, and parts of Louisiana from the eastern states.

Symbol and Strategy

Losing Vicksburg on July 4 hurt Confederate morale and supply lines. Combined with Gettysburg, it convinced many that the Union now had the upper hand.

Cause and Effect: Linking Vicksburg to the Bigger War

Use this activity to connect the fall of Vicksburg to broader Union strategy.

List the Causes: In your own words, write down 3 main reasons the Union was able to capture Vicksburg. Use phrases like:

“Effective use of the navy…”
“Grant’s decision to cross south of the city…”
“The long siege that…”

List the Effects: Next, write down 3 major effects of the fall of Vicksburg on the overall war. For example:

“The Confederacy was split in two because…”
“Union forces could now move along the Mississippi to…”
“Combined with Gettysburg, this changed Northern morale by…”

Connect Them: Draw arrows matching each cause to at least one effect. For example, connect “Union control of the Mississippi” to “cutting Confederate supply routes from Texas.”

Challenge Question: In 2–3 sentences, explain how the Vicksburg Campaign shows the difference between tactical success (winning battles) and strategic success (changing the overall direction of the war).

Key Terms Review: Vicksburg and the Mississippi

Flip these cards to review the most important terms from the Vicksburg Campaign and its impact.

Vicksburg: A Confederate fortress city on high bluffs above the Mississippi River in Mississippi. Its capture by Union forces on July 4, 1863, gave the Union full control of the river and split the Confederacy.
Vicksburg Campaign: A series of maneuvers and battles in late 1862 and 1863, led by Ulysses S. Grant, using joint army-navy operations, a bold river crossing south of the city, inland battles, and a final siege to capture Vicksburg.
Riverine warfare: Military operations that use naval forces on rivers to support land campaigns. At Vicksburg, Union gunboats and transports helped move troops, supply them, and attack Confederate river defenses.
Siege: A method of warfare where an army surrounds a place, cuts off supplies and reinforcements, and slowly forces surrender. Grant’s siege of Vicksburg lasted from late May until July 4, 1863.
Ulysses S. Grant: Union general who led the Vicksburg Campaign. His persistence, use of joint operations, and bold decision to cross south of Vicksburg were central to Union victory in the West.
Admiral David D. Porter: Union naval commander whose gunboats and ironclads supported Grant at Vicksburg, including running past Confederate batteries and ferrying troops across the Mississippi.
July 4, 1863: The date Vicksburg surrendered to Grant, one day after the end of the Battle of Gettysburg. Together, these events marked a major strategic turning point in the Civil War.
Splitting the Confederacy: The strategic effect of Union control of the Mississippi River: it separated Texas, Arkansas, and parts of Louisiana from the eastern Confederate states, cutting key supply routes.

Key Terms

Siege: A military strategy of surrounding a place, cutting off supplies, and forcing surrender over time instead of taking it by quick assault.
Vicksburg: Confederate stronghold city on the Mississippi River whose surrender to Union forces on July 4, 1863, gave the Union full control of the river.
Riverine warfare: Use of naval forces on rivers to support land operations, protect supply lines, and attack enemy positions.
Ulysses S. Grant: Union general who led successful campaigns in the Western Theater, including Vicksburg, and later became overall Union commander and U.S. president.
Vicksburg Campaign: Grant’s 1862–1863 operations combining maneuvers, battles, and a siege to capture Vicksburg and open the Mississippi River.
Admiral David D. Porter: Union naval officer who commanded gunboats and ironclads on the Mississippi, working closely with Grant at Vicksburg.
Splitting the Confederacy: Strategic goal of Union leaders to divide Confederate territory, especially by controlling the Mississippi River, to weaken Southern resistance.
High-water mark of the Confederacy: A phrase often applied to Gettysburg, describing the furthest point of Confederate military advance before the tide turned against them.