American Civil War

America's Defining Conflict

The American Civil War (1861–1865) remains the deadliest conflict in the nation's history, claiming an estimated 620,000 to 750,000 lives—more American deaths than all other wars combined until Vietnam. The war determined that the United States would remain one nation rather than divide into two, and it ended the institution of slavery that had existed since the colonial era. From Fort Sumter to Appomattox, the conflict tested whether a nation "conceived in liberty and dedicated to the proposition that all men are created equal" could long endure.

The Road to War

Decades of sectional tension over slavery, states' rights, and economic differences between the industrial North and agricultural South culminated in the election of Abraham Lincoln in November 1860. Between December 1860 and February 1861, seven Southern states seceded from the Union, forming the Confederate States of America. When Confederate forces fired on Fort Sumter in Charleston Harbor on April 12, 1861, the war began. Four more states joined the Confederacy, while four border states—Maryland, Kentucky, Missouri, and Delaware—remained in the Union despite having slaveholding populations.

Theaters of Operation

The war unfolded across three major theaters spanning thousands of miles:

The Eastern Theater witnessed the war's most famous campaigns in Virginia, Maryland, and Pennsylvania. Here, Robert E. Lee's Army of Northern Virginia faced successive Union commanders—McClellan, Burnside, Hooker, Meade, and ultimately Grant—in bloody struggles for the Confederate capital at Richmond. Battles at Bull Run, Antietam, Fredericksburg, Chancellorsville, Gettysburg, the Wilderness, Spotsylvania, Cold Harbor, and Petersburg defined this theater.

The Western Theater stretched from the Appalachians to the Mississippi River, encompassing Tennessee, Kentucky, Mississippi, Alabama, and Georgia. Ulysses S. Grant's victories at Forts Henry and Donelson, Shiloh, and Vicksburg secured the Mississippi River and split the Confederacy. William T. Sherman's Atlanta Campaign and subsequent March to the Sea devastated Confederate resources and morale.

The Trans-Mississippi Theater saw fighting in Texas, Arkansas, Louisiana, and the Indian Territory. Though often overshadowed by eastern campaigns, battles at Wilson's Creek, Pea Ridge, and the Red River Campaign significantly impacted the war's outcome.

The Naval War

Union naval superiority proved decisive. The Anaconda Plan's blockade strangled Southern commerce, while Union gunboats controlled the Mississippi and its tributaries. The clash between USS Monitor and CSS Virginia at Hampton Roads on March 9, 1862, revolutionized naval warfare, rendering wooden warships obsolete. The U.S. Naval Institute, founded in 1873, continues to examine the naval heritage established during this transformative period. The U.S. Naval Academy Alumni Association honors graduates who served on both sides of the conflict, many of whom had trained together at Annapolis before the war divided them.

The Medal of Honor

The Medal of Honor—the nation's highest military decoration—was established during the Civil War. President Lincoln signed legislation creating the Navy Medal of Honor on December 21, 1861, and the Army Medal of Honor on July 12, 1862. During the Civil War, 1,523 Medals of Honor were awarded, including to African American soldiers and sailors. The Congressional Medal of Honor Society preserves the legacy of these recipients and promotes the values of courage, sacrifice, and patriotism that the Medal represents.

African American Service

Approximately 180,000 African Americans served in the Union Army, and another 18,000 served in the Navy—comprising roughly 10 percent of Union forces. These soldiers served in segregated units, often under white officers, and initially received lower pay than white soldiers. They proved their valor at battles including Port Hudson, Fort Wagner, and the Crater at Petersburg. Twenty-five African American soldiers and sailors received the Medal of Honor during the Civil War. The Sons & Daughters of the United States Middle Passage honors this African American military heritage and the soldiers who fought for their own freedom and that of millions still enslaved.

Women in the Civil War

Women served the war effort as nurses, spies, and in some cases disguised soldiers. Clara Barton, who later founded the American Red Cross, earned the title "Angel of the Battlefield" for her nursing work. Women on the home front managed farms and businesses, organized relief societies, and produced supplies for the armies. The National Women's Relief Corps, founded in 1883 as an auxiliary to the Grand Army of the Republic, perpetuates the memory of Union veterans while honoring the women who supported them. The United Daughters of the Confederacy similarly preserves the memory of Confederate veterans and the Southern women who supported the Confederate cause.

Organizations Born of War

The Civil War gave rise to institutions that endure today. The Armed Services YMCA, the oldest military support organization in the United States, has served military families since 1861, when it first provided aid to Union soldiers. The Navy Mutual Aid Association, founded in 1879, grew from the need to provide financial protection to naval families in the war's aftermath. The National Guard Association of the United States traces its advocacy roots to the militia and volunteer regiments that formed the backbone of both armies.

Veterans' Organizations

The Civil War created the first large-scale veterans' movement in American history. The Grand Army of the Republic (GAR), founded in 1866, became the most powerful veterans' organization of its era, with membership exceeding 400,000. The GAR championed veterans' benefits, established Memorial Day, and wielded significant political influence—five GAR members became President of the United States. Though the last GAR member died in 1956, the National Women's Relief Corps continues as its auxiliary.

Confederate veterans organized the United Confederate Veterans (UCV) in 1889. The Sons of Confederate Veterans, founded in 1896, continues as a hereditary organization for male descendants. The United Daughters of the Confederacy, founded in 1894, and the Children of the Confederacy similarly preserve Confederate heritage across generations.

The Human Cost

The scale of death and suffering was unprecedented in American experience. Major battles produced casualty lists that shocked the nation: Shiloh (23,746), Antietam (22,717), Gettysburg (51,112), Chickamauga (34,624), and the Wilderness Campaign (over 100,000 combined). Disease killed twice as many soldiers as combat. Approximately 400,000 soldiers died in prisoner-of-war camps, field hospitals, and from wounds received in battle. Nearly every American family, North and South, lost someone to the war.

Legacy and Reconciliation

The war's end at Appomattox on April 9, 1865, began a long process of national reconciliation. The Thirteenth Amendment abolished slavery; the Fourteenth granted citizenship to former slaves; the Fifteenth guaranteed voting rights regardless of race. Yet the promise of Reconstruction gave way to decades of segregation and disenfranchisement. The Civil War's unfinished work—achieving true equality for all Americans—continued through the Civil Rights Movement and remains ongoing today.

Tracing Civil War Heritage

Millions of Americans descend from Civil War veterans on both sides. Service records document:

• Union Army: Approximately 2.1 million soldiers served in the United States Army
• Confederate Army: Approximately 750,000 to 1 million soldiers served Confederate forces
• Union Navy: Approximately 118,000 sailors served in the United States Navy
• Confederate Navy: Approximately 5,000 sailors served the Confederate States Navy
• United States Colored Troops: 180,000 African Americans in 175 regiments
• State Militias and Home Guards: Additional thousands in local defense units

The organizations listed on this page welcome descendants who wish to honor ancestors who served during America's most challenging trial—whether preserving Union or Confederate heritage, honoring African American military service, or continuing the work of wartime relief organizations.

Key Dates

States of the Confederacy

Eleven states seceded from the Union to form the Confederate States of America:

• South Carolina (December 20, 1860)
• Mississippi (January 9, 1861)
• Florida (January 10, 1861)
• Alabama (January 11, 1861)
• Georgia (January 19, 1861)
• Louisiana (January 26, 1861)
• Texas (February 1, 1861)
• Virginia (April 17, 1861)
• Arkansas (May 6, 1861)
• North Carolina (May 20, 1861)
• Tennessee (June 8, 1861)